Added RuboCop cops for checking DB migrations

See merge request !4906

[ci skip]

Insert notification settings dropdown into groups

## Display notification settings dropdown for groups

part of #3359   

![groups](/uploads/d61648236b81b0cca55fa2d73758f0df/groups.png)
![Screenshot_from_2016-06-29_10-58-37](/uploads/7be05ea6002932c094a81b25a308fd62/Screenshot_from_2016-06-29_10-58-37.png)  
![small](/uploads/6f2b556d734c870e358f6f56618a0bab/small.png)

See merge request !4857

Fixed search field blur not removing focus

## What does this MR do?

Adds a blur event to remove focus styling from the search input.

Any particular reason we were looking for clicks on the document? I can't see why we would be.

## What are the relevant issue numbers?

Closes #18670 

## Screenshots (if relevant)

![tab](/uploads/4c74d4f76ec7b45bfcf581606d2defb5/tab.gif)

See merge request !4704

optimize png images losslessly using zopflipng

Resend https://github.com/gitlabhq/gitlabhq/pull/10354#issuecomment-222194091

Optimized 246 png images losslessly using Google's zopflipng.
```
 app/assets/images/auth_buttons/azure_64.png        | Bin 986 -> 695 bytes
 app/assets/images/auth_buttons/bitbucket_64.png    | Bin 2163 -> 2161 bytes
 app/assets/images/auth_buttons/facebook_64.png     | Bin 2970 -> 870 bytes
 app/assets/images/auth_buttons/github_64.png       | Bin 2625 -> 1151 bytes
 app/assets/images/auth_buttons/gitlab_64.png       | Bin 2849 -> 2070 bytes
 app/assets/images/auth_buttons/google_64.png       | Bin 5281 -> 4366 bytes
 app/assets/images/auth_buttons/twitter_64.png      | Bin 4835 -> 3110 bytes
 app/assets/images/bg_fallback.png                  | Bin 167 -> 167 bytes
 app/assets/images/dark-scheme-preview.png          | Bin 3996 -> 3992 bytes
 app/assets/images/emoji.png                        | Bin 263533 -> 263346 bytes
 app/assets/images/emoji@2x.png                     | Bin 690504 -> 689076 bytes
 app/assets/images/gitlab_logo.png                  | Bin 5189 -> 3616 bytes
 app/assets/images/gitorious-logo-black.png         | Bin 809 -> 631 bytes
 app/assets/images/gitorious-logo-blue.png          | Bin 495 -> 201 bytes
 app/assets/images/icon-link.png                    | Bin 1128 -> 729 bytes
 app/assets/images/images.png                       | Bin 5849 -> 5806 bytes
 app/assets/images/monokai-scheme-preview.png       | Bin 3711 -> 3708 bytes
 app/assets/images/msapplication-tile.png           | Bin 5798 -> 4328 bytes
 app/assets/images/no_avatar.png                    | Bin 621 -> 621 bytes
 app/assets/images/no_group_avatar.png              | Bin 942 -> 939 bytes
 app/assets/images/slider_handles.png               | Bin 1377 -> 1341 bytes
 app/assets/images/touch-icon-ipad-retina.png       | Bin 8130 -> 5662 bytes
 app/assets/images/touch-icon-ipad.png              | Bin 3493 -> 2465 bytes
 app/assets/images/touch-icon-iphone-retina.png     | Bin 4997 -> 3460 bytes
 app/assets/images/touch-icon-iphone.png            | Bin 2766 -> 1949 bytes
 doc/administration/img/housekeeping_settings.png   | Bin 23856 -> 19347 bytes
 .../img/build_artifacts_browser.png                | Bin 89132 -> 82102 bytes
 .../img/build_artifacts_browser_button.png         | Bin 11614 -> 7230 bytes
 doc/ci/img/builds_tab.png                          | Bin 3845 -> 3047 bytes
 doc/ci/img/features_settings.png                   | Bin 18691 -> 15809 bytes
 doc/ci/quick_start/img/build_log.png               | Bin 63272 -> 52482 bytes
 doc/ci/quick_start/img/builds_status.png           | Bin 49121 -> 41838 bytes
 doc/ci/quick_start/img/new_commit.png              | Bin 9033 -> 7587 bytes
 doc/ci/quick_start/img/runners_activated.png       | Bin 27597 -> 22822 bytes
 .../img/single_commit_status_pending.png           | Bin 36431 -> 29981 bytes
 doc/ci/quick_start/img/status_pending.png          | Bin 19782 -> 16205 bytes
 doc/ci/runners/project_specific.png                | Bin 31408 -> 30196 bytes
 doc/ci/runners/shared_runner.png                   | Bin 18366 -> 17797 bytes
 doc/ci/runners/shared_to_specific_admin.png        | Bin 5897 -> 5715 bytes
 doc/ci/triggers/img/builds_page.png                | Bin 39713 -> 33324 bytes
 doc/ci/triggers/img/trigger_single_build.png       | Bin 2895 -> 2387 bytes
 doc/ci/triggers/img/trigger_variables.png          | Bin 5418 -> 4433 bytes
 doc/ci/triggers/img/triggers_page.png              | Bin 15889 -> 12943 bytes
 doc/container_registry/img/container_registry.png  | Bin 354050 -> 222782 bytes
 doc/container_registry/img/project_feature.png     | Bin 392842 -> 248750 bytes
 .../branded_login_page/appearance.png              | Bin 365120 -> 156228 bytes
 .../branded_login_page/custom_sign_in.png          | Bin 314111 -> 166674 bytes
 .../branded_login_page/default_login_page.png      | Bin 292731 -> 150538 bytes
 doc/development/gitlab_architecture_diagram.png    | Bin 46947 -> 23831 bytes
 .../basicsimages/add_new_merge_request.png         | Bin 9467 -> 9003 bytes
 doc/gitlab-basics/basicsimages/add_sshkey.png      | Bin 1463 -> 1394 bytes
 doc/gitlab-basics/basicsimages/branch_info.png     | Bin 7978 -> 7572 bytes
 doc/gitlab-basics/basicsimages/branch_name.png     | Bin 2199 -> 2137 bytes
 doc/gitlab-basics/basicsimages/branches.png        | Bin 3653 -> 3548 bytes
 .../basicsimages/button-create-mr.png              | Bin 6154 -> 5927 bytes
 .../basicsimages/click-on-new-group.png            | Bin 2063 -> 1957 bytes
 doc/gitlab-basics/basicsimages/commit_changes.png  | Bin 5567 -> 4941 bytes
 doc/gitlab-basics/basicsimages/commit_message.png  | Bin 5707 -> 5103 bytes
 doc/gitlab-basics/basicsimages/commits.png         | Bin 4258 -> 4112 bytes
 .../basicsimages/compare_branches.png              | Bin 1624 -> 1520 bytes
 doc/gitlab-basics/basicsimages/create_file.png     | Bin 2524 -> 2451 bytes
 doc/gitlab-basics/basicsimages/create_group.png    | Bin 3224 -> 3184 bytes
 doc/gitlab-basics/basicsimages/edit_file.png       | Bin 2259 -> 2221 bytes
 doc/gitlab-basics/basicsimages/file_located.png    | Bin 3156 -> 3078 bytes
 doc/gitlab-basics/basicsimages/file_name.png       | Bin 2544 -> 2412 bytes
 doc/gitlab-basics/basicsimages/find_file.png       | Bin 8840 -> 8426 bytes
 doc/gitlab-basics/basicsimages/find_group.png      | Bin 6159 -> 5897 bytes
 doc/gitlab-basics/basicsimages/fork.png            | Bin 1046 -> 896 bytes
 doc/gitlab-basics/basicsimages/group_info.png      | Bin 16217 -> 15479 bytes
 doc/gitlab-basics/basicsimages/groups.png          | Bin 4857 -> 4752 bytes
 doc/gitlab-basics/basicsimages/https.png           | Bin 2887 -> 2822 bytes
 doc/gitlab-basics/basicsimages/image_file.png      | Bin 2939 -> 2796 bytes
 doc/gitlab-basics/basicsimages/issue_title.png     | Bin 9059 -> 8311 bytes
 doc/gitlab-basics/basicsimages/issues.png          | Bin 4332 -> 4153 bytes
 doc/gitlab-basics/basicsimages/key.png             | Bin 1264 -> 1177 bytes
 doc/gitlab-basics/basicsimages/merge_requests.png  | Bin 4381 -> 4213 bytes
 .../basicsimages/new_merge_request.png             | Bin 3227 -> 3162 bytes
 doc/gitlab-basics/basicsimages/new_project.png     | Bin 2319 -> 2234 bytes
 doc/gitlab-basics/basicsimages/newbranch.png       | Bin 1314 -> 1244 bytes
 doc/gitlab-basics/basicsimages/paste_sshkey.png    | Bin 8620 -> 7699 bytes
 .../basicsimages/profile_settings.png              | Bin 1194 -> 1101 bytes
 doc/gitlab-basics/basicsimages/project_info.png    | Bin 21862 -> 21041 bytes
 .../basicsimages/public_file_link.png              | Bin 3038 -> 3023 bytes
 doc/gitlab-basics/basicsimages/select-group.png    | Bin 6075 -> 6034 bytes
 doc/gitlab-basics/basicsimages/select-group2.png   | Bin 5049 -> 5040 bytes
 doc/gitlab-basics/basicsimages/select_branch.png   | Bin 12213 -> 11207 bytes
 doc/gitlab-basics/basicsimages/select_project.png  | Bin 16832 -> 16176 bytes
 doc/gitlab-basics/basicsimages/settings.png        | Bin 4321 -> 4149 bytes
 doc/gitlab-basics/basicsimages/shh_keys.png        | Bin 4981 -> 4782 bytes
 .../basicsimages/submit_new_issue.png              | Bin 9083 -> 8644 bytes
 .../basicsimages/title_description_mr.png          | Bin 12749 -> 11919 bytes
 doc/gitlab-basics/basicsimages/white_space.png     | Bin 3707 -> 2192 bytes
 doc/integration/img/akismet_settings.png           | Bin 55837 -> 26625 bytes
 .../img/enabled-oauth-sign-in-sources.png          | Bin 49081 -> 21767 bytes
 doc/integration/img/facebook_api_keys.png          | Bin 125921 -> 85832 bytes
 doc/integration/img/facebook_app_settings.png      | Bin 134387 -> 68086 bytes
 doc/integration/img/facebook_website_url.png       | Bin 42292 -> 19823 bytes
 doc/integration/img/github_app.png                 | Bin 75297 -> 55591 bytes
 doc/integration/img/gitlab_app.png                 | Bin 55325 -> 30963 bytes
 .../img/gmail_action_buttons_for_gitlab.png        | Bin 17321 -> 16020 bytes
 doc/integration/img/google_app.png                 | Bin 52669 -> 29154 bytes
 .../img/oauth_provider_admin_application.png       | Bin 40579 -> 33440 bytes
 .../img/oauth_provider_application_form.png        | Bin 27974 -> 23048 bytes
 .../img/oauth_provider_application_id_secret.png   | Bin 33901 -> 27673 bytes
 .../img/oauth_provider_authorized_application.png  | Bin 32225 -> 26622 bytes
 .../img/oauth_provider_user_wide_applications.png  | Bin 40632 -> 33337 bytes
 doc/integration/img/twitter_app_api_keys.png       | Bin 72200 -> 36921 bytes
 doc/integration/img/twitter_app_details.png        | Bin 121621 -> 64686 bytes
 doc/markdown/img/logo.png                          | Bin 11097 -> 9509 bytes
 doc/monitoring/img/health_check_token.png          | Bin 10884 -> 6630 bytes
 .../performance/img/grafana_dashboard_dropdown.png | Bin 29419 -> 14368 bytes
 .../performance/img/grafana_dashboard_import.png   | Bin 40974 -> 18267 bytes
 .../img/grafana_data_source_configuration.png      | Bin 53402 -> 26060 bytes
 .../performance/img/grafana_data_source_empty.png  | Bin 44058 -> 21821 bytes
 .../performance/img/grafana_save_icon.png          | Bin 16024 -> 9107 bytes
 .../img/metrics_gitlab_configuration_settings.png  | Bin 45148 -> 37228 bytes
 doc/profile/2fa.png                                | Bin 23415 -> 22047 bytes
 doc/profile/2fa_auth.png                           | Bin 15569 -> 14535 bytes
 doc/project_services/img/builds_emails_service.png | Bin 41222 -> 33943 bytes
 .../img/jira_add_gitlab_commit_message.png         | Bin 57136 -> 46590 bytes
 .../img/jira_add_user_to_group.png                 | Bin 59251 -> 41994 bytes
 doc/project_services/img/jira_create_new_group.png | Bin 41294 -> 32934 bytes
 .../img/jira_create_new_group_name.png             | Bin 12535 -> 9054 bytes
 doc/project_services/img/jira_create_new_user.png  | Bin 26532 -> 21081 bytes
 doc/project_services/img/jira_group_access.png     | Bin 46028 -> 32210 bytes
 doc/project_services/img/jira_issue_closed.png     | Bin 92601 -> 77028 bytes
 doc/project_services/img/jira_issue_reference.png  | Bin 39942 -> 36188 bytes
 doc/project_services/img/jira_issues_workflow.png  | Bin 105237 -> 87067 bytes
 .../img/jira_merge_request_close.png               | Bin 111150 -> 102835 bytes
 doc/project_services/img/jira_project_name.png     | Bin 60598 -> 41572 bytes
 ...jira_reference_commit_message_in_jira_issue.png | Bin 42452 -> 33706 bytes
 doc/project_services/img/jira_service.png          | Bin 59082 -> 56834 bytes
 .../img/jira_service_close_issue.png               | Bin 88433 -> 79569 bytes
 doc/project_services/img/jira_service_page.png     | Bin 49122 -> 36280 bytes
 .../img/jira_submit_gitlab_merge_request.png       | Bin 63063 -> 51913 bytes
 .../img/jira_user_management_link.png              | Bin 58211 -> 43095 bytes
 .../img/jira_workflow_screenshot.png               | Bin 121534 -> 111093 bytes
 doc/project_services/img/redmine_configuration.png | Bin 21061 -> 16973 bytes
 .../img/services_templates_redmine_example.png     | Bin 17351 -> 13936 bytes
 doc/raketasks/backup_hrz.png                       | Bin 21955 -> 8907 bytes
 doc/raketasks/check_repos_output.png               | Bin 73786 -> 35333 bytes
 .../img/two_factor_authentication_settings.png     | Bin 20399 -> 16807 bytes
 doc/web_hooks/ssl.png                              | Bin 77165 -> 39120 bytes
 .../img/add_new_user_to_project_settings.png       | Bin 22822 -> 18149 bytes
 .../add-user/img/add_user_email_accept.png         | Bin 22961 -> 22877 bytes
 doc/workflow/add-user/img/add_user_email_ready.png | Bin 40305 -> 40207 bytes
 .../add-user/img/add_user_email_search.png         | Bin 45884 -> 45798 bytes
 .../add-user/img/add_user_give_permissions.png     | Bin 56480 -> 56380 bytes
 ...dd_user_import_members_from_another_project.png | Bin 38874 -> 38778 bytes
 .../add-user/img/add_user_imported_members.png     | Bin 37873 -> 37835 bytes
 .../add-user/img/add_user_list_members.png         | Bin 24427 -> 24337 bytes
 .../add-user/img/add_user_members_menu.png         | Bin 42319 -> 42224 bytes
 .../add-user/img/add_user_search_people.png        | Bin 39941 -> 39844 bytes
 doc/workflow/award_emoji.png                       | Bin 16926 -> 9939 bytes
 doc/workflow/ci_mr.png                             | Bin 40065 -> 29571 bytes
 doc/workflow/close_issue_mr.png                    | Bin 146292 -> 82595 bytes
 doc/workflow/environment_branches.png              | Bin 40210 -> 20745 bytes
 doc/workflow/forking/branch_select.png             | Bin 55352 -> 27299 bytes
 doc/workflow/forking/merge_request.png             | Bin 60597 -> 31560 bytes
 doc/workflow/four_stages.png                       | Bin 20934 -> 10003 bytes
 doc/workflow/git_pull.png                          | Bin 167056 -> 94405 bytes
 doc/workflow/gitdashflow.png                       | Bin 184726 -> 131491 bytes
 doc/workflow/github_flow.png                       | Bin 20600 -> 10251 bytes
 doc/workflow/gitlab_flow.png                       | Bin 90883 -> 70871 bytes
 doc/workflow/good_commit.png                       | Bin 28433 -> 13131 bytes
 doc/workflow/groups/add_member_to_group.png        | Bin 138184 -> 78060 bytes
 doc/workflow/groups/group_dashboard.png            | Bin 107332 -> 59446 bytes
 doc/workflow/groups/group_with_two_projects.png    | Bin 129319 -> 73101 bytes
 doc/workflow/groups/max_access_level.png           | Bin 135354 -> 74947 bytes
 doc/workflow/groups/new_group_button.png           | Bin 185406 -> 108482 bytes
 doc/workflow/groups/new_group_form.png             | Bin 106491 -> 58860 bytes
 .../groups/other_group_sees_shared_project.png     | Bin 118382 -> 64447 bytes
 doc/workflow/groups/override_access_level.png      | Bin 157193 -> 90122 bytes
 doc/workflow/groups/project_members_via_group.png  | Bin 151339 -> 86260 bytes
 doc/workflow/groups/share_project_with_groups.png  | Bin 118868 -> 65633 bytes
 doc/workflow/groups/transfer_project.png           | Bin 164958 -> 92115 bytes
 doc/workflow/img/award_emoji_select.png            | Bin 65985 -> 49296 bytes
 .../img/award_emoji_votes_least_popular.png        | Bin 144501 -> 116715 bytes
 .../img/award_emoji_votes_most_popular.png         | Bin 136577 -> 108775 bytes
 .../img/award_emoji_votes_sort_options.png         | Bin 162251 -> 131659 bytes
 doc/workflow/img/cherry_pick_changes_commit.png    | Bin 353067 -> 304098 bytes
 .../img/cherry_pick_changes_commit_modal.png       | Bin 312659 -> 264883 bytes
 doc/workflow/img/cherry_pick_changes_mr.png        | Bin 252085 -> 212267 bytes
 doc/workflow/img/cherry_pick_changes_mr_modal.png  | Bin 225569 -> 186597 bytes
 doc/workflow/img/file_finder_find_button.png       | Bin 30974 -> 25458 bytes
 doc/workflow/img/file_finder_find_file.png         | Bin 42658 -> 35114 bytes
 .../img/forking_workflow_choose_namespace.png      | Bin 70405 -> 59114 bytes
 doc/workflow/img/forking_workflow_fork_button.png  | Bin 26438 -> 20750 bytes
 .../img/forking_workflow_path_taken_error.png      | Bin 22380 -> 17978 bytes
 doc/workflow/img/new_branch_from_issue.png         | Bin 120622 -> 54607 bytes
 doc/workflow/img/revert_changes_commit.png         | Bin 360098 -> 233750 bytes
 doc/workflow/img/revert_changes_commit_modal.png   | Bin 327932 -> 205046 bytes
 doc/workflow/img/revert_changes_mr.png             | Bin 367881 -> 241051 bytes
 doc/workflow/img/revert_changes_mr_modal.png       | Bin 335010 -> 211022 bytes
 doc/workflow/img/todos_icon.png                    | Bin 6320 -> 3843 bytes
 doc/workflow/img/todos_index.png                   | Bin 184839 -> 152040 bytes
 .../img/web_editor_new_branch_dropdown.png         | Bin 34233 -> 20436 bytes
 doc/workflow/img/web_editor_new_branch_page.png    | Bin 21618 -> 11245 bytes
 .../img/web_editor_new_directory_dialog.png        | Bin 26145 -> 13339 bytes
 .../img/web_editor_new_directory_dropdown.png      | Bin 33714 -> 20007 bytes
 doc/workflow/img/web_editor_new_file_dropdown.png  | Bin 34978 -> 20680 bytes
 doc/workflow/img/web_editor_new_file_editor.png    | Bin 128658 -> 66261 bytes
 doc/workflow/img/web_editor_new_push_widget.png    | Bin 11220 -> 7076 bytes
 doc/workflow/img/web_editor_new_tag_dropdown.png   | Bin 33753 -> 20080 bytes
 doc/workflow/img/web_editor_new_tag_page.png       | Bin 75536 -> 36610 bytes
 .../img/web_editor_start_new_merge_request.png     | Bin 14352 -> 8596 bytes
 doc/workflow/img/web_editor_upload_file_dialog.png | Bin 46219 -> 21502 bytes
 .../img/web_editor_upload_file_dropdown.png        | Bin 34835 -> 20651 bytes
 .../bitbucket_import_select_project.png            | Bin 16121 -> 15288 bytes
 .../fogbugz_importer/fogbugz_import_finished.png   | Bin 53276 -> 30266 bytes
 .../fogbugz_importer/fogbugz_import_login.png      | Bin 44444 -> 20797 bytes
 .../fogbugz_import_select_fogbogz.png              | Bin 35415 -> 20526 bytes
 .../fogbugz_import_select_project.png              | Bin 62552 -> 34836 bytes
 .../fogbugz_importer/fogbugz_import_user_map.png   | Bin 157856 -> 77208 bytes
 .../importing/gitlab_importer/importer.png         | Bin 40778 -> 18366 bytes
 .../importing/gitlab_importer/new_project_page.png | Bin 72663 -> 33589 bytes
 .../img/import_projects_from_github_importer.png   | Bin 28033 -> 22711 bytes
 ...mport_projects_from_github_new_project_page.png | Bin 17225 -> 13668 bytes
 doc/workflow/merge_commits.png                     | Bin 41422 -> 22181 bytes
 doc/workflow/merge_request.png                     | Bin 169503 -> 98070 bytes
 doc/workflow/merge_requests/commit_compare.png     | Bin 110376 -> 65010 bytes
 doc/workflow/merge_requests/merge_request_diff.png | Bin 166226 -> 103239 bytes
 .../merge_request_diff_without_whitespace.png      | Bin 121476 -> 71896 bytes
 doc/workflow/merge_when_build_succeeds/enable.png  | Bin 151112 -> 68769 bytes
 doc/workflow/merge_when_build_succeeds/status.png  | Bin 180318 -> 82655 bytes
 doc/workflow/messy_flow.png                        | Bin 33829 -> 19314 bytes
 doc/workflow/milestones/form.png                   | Bin 88591 -> 84872 bytes
 doc/workflow/milestones/group_form.png             | Bin 77087 -> 74429 bytes
 doc/workflow/mr_inline_comments.png                | Bin 193311 -> 117313 bytes
 doc/workflow/notifications/settings.png            | Bin 90986 -> 59256 bytes
 doc/workflow/production_branch.png                 | Bin 21716 -> 10946 bytes
 .../protected_branches/protected_branches1.png     | Bin 170113 -> 155815 bytes
 .../protected_branches/protected_branches2.png     | Bin 25851 -> 23208 bytes
 doc/workflow/rebase.png                            | Bin 123041 -> 68976 bytes
 doc/workflow/release_branches.png                  | Bin 44173 -> 22163 bytes
 doc/workflow/releases/new_tag.png                  | Bin 154755 -> 87330 bytes
 doc/workflow/releases/tags.png                     | Bin 165449 -> 93016 bytes
 doc/workflow/remove_checkbox.png                   | Bin 22272 -> 12339 bytes
 doc/workflow/share_with_group.png                  | Bin 53784 -> 50450 bytes
 doc/workflow/shortcuts.png                         | Bin 108255 -> 108209 bytes
 .../wip_merge_requests/blocked_accept_button.png   | Bin 65231 -> 32720 bytes
 doc/workflow/wip_merge_requests/mark_as_wip.png    | Bin 41549 -> 21640 bytes
 doc/workflow/wip_merge_requests/unmark_as_wip.png  | Bin 32151 -> 16606 bytes
 public/apple-touch-icon-precomposed.png            | Bin 11097 -> 9509 bytes
 public/apple-touch-icon.png                        | Bin 11097 -> 9509 bytes
 spec/fixtures/dk.png                               | Bin 1143 -> 1062 bytes
```

cc @connorshea

See merge request !4325

Changes calendar activities to use target reference

## What does this MR do?

Uses the targets reference in the calendar activities list. Previously it was using `#` which is wrong for merge requests.

## Screenshots (if relevant)

![Screen_Shot_2016-06-29_at_14.29.08](/uploads/4c52bbc7ca68d7b25e5bfb11ea55eef7/Screen_Shot_2016-06-29_at_14.29.08.png)

See merge request !4992

Removed fade when filtering results

## What does this MR do?

Removes the `opacity` change when filtering results seeing as we now do `Turbolinks.visit` it isn't required.

Best way to see issue - filter issues & then go back. Will still have opacity styling.

See merge request !4932

Bugzilla Integration

## What does this MR do?
Adds Bugzilla as a project service for external issue tracking

## Are there points in the code the reviewer needs to double check?

## Why was this MR needed?
Provides a notable Bugzilla option for use as an external issue tracker.  Existing Custom Issue tracker can be used to setup Bugzilla but this makes it clear that Bugzilla is an option.

## What are the relevant issue numbers?
Closes #14669

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] API support added
- Tests
  - [x] Added for this feature/bug
  - [x] All builds are passing
- [x] Conform by the [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)


See merge request !4930

Add fog-rackspace microgem to support backups using rackspace provider

## What does this MR do?

Adds fog-rackspace gem to Gemfile.

## Why was this MR needed?

Because fog moved the rackspace provider to separate gem.

## What are the relevant issue numbers?

#19197

See merge request !4986

Use update_columns to by_pass all the dirty code on active_record

See merge request !4985

There are currently two cops for this:

* Migration/AddIndex: checks if indexes are added concurrently
* Migration/ColumnWithDefault: checks if columns with default values are
  added in a concurrent manner

Both cops are fairly simple and make no attempt at correcting the code
as this is quite hard to do (e.g. modifications may need to be applied
in various places in the same file). They however should provide enough
to catch people ignoring the comments in generated migrations telling
them to use add_concurrent_index or add_column_with_default.

We think this is valid because we’re just storing new data that always will be valid

Reduce overhead and optimize ProjectTeam#max_member_access performance

See merge request !4973

The previous implementation would load the entire team member list and their
respective attributes. Now we only search for the user's specific
access level.

In gitlab-com/operations#42, this reduces the overall overhead of rendering
the issue from 28% to 20%.

First step of optimizing #19273

rebased with latest changes from master

Rebased to resolve merge conflicts

Requested in #14669

Added note to changelog

PipelinesFinder use git cached data

See merge request !4984

Fixes missing avatar on system notes

Closes #17295


![Screen_Shot_2016-06-27_at_12.50.50_PM](/uploads/b142226e608ccfe751a9b6059f57c9ec/Screen_Shot_2016-06-27_at_12.50.50_PM.jpg)

See merge request !4954

Markdown toolbar inserts code blocks

## What does this MR do?

Adds the ability to insert code blocks with the markdown toolbar buttons. This is done by selecting the block & then clicking the code button.

## What are the relevant issue numbers?

Closes #19173 


See merge request !4950

Fixed avatar alignment in new MR view

## What does this MR do?

Fixes the alignment of the avatar in new MR view.
Closes #19076 

## Screenshots (if relevant)

![Screen_Shot_2016-06-24_at_12.53.58](/uploads/fc94faf2e48f194852693b7ae79e8fa3/Screen_Shot_2016-06-24_at_12.53.58.png)

See merge request !4901

Workhorse to serve email diffs

See merge request !4590

Show basic system info on admin panel. Closes #18886

![Screen_Shot_2016-06-23_at_10.57.07_AM](/uploads/df33bc3dc36ceaf86f5e479ca15b83f3/Screen_Shot_2016-06-23_at_10.57.07_AM.png)

See merge request !4858

Fix group visibility form layout in application settings

## What does this MR do?

This fixes UI consistency related to setting group visibility levels in application settings. See screenshots.

## Screenshots (if relevant)

#### Before

![visiblity_consistency](/uploads/9cf9b517e25cd661ac61bdd7ca2d82f4/visiblity_consistency.png)

#### After

![group_visibility_after](/uploads/7b317684d047716f2aa5e60d19a4281b/group_visibility_after.png)

See merge request !4848