Admin area: doesn't show a note when it's empty

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/12636

See merge request !133

Allow empty Mysql password on CI

[ci skip]

See merge request !2558

GitLab 8.4 uses gitlab-shell v2.6.10

While upgrading to GitLab 8.3 to 8.4 there was a warning massage for using GitLab 8.3 with gitlab-shell v2.6.9 so I changed gitlab-shell version to v2.6.10 and it worked.

See merge request !2555

Fix broken codeblocks in ci/yaml documentation



See merge request !2554

[ci skip]

Remove 8.4 unreleased note from changelog



See merge request !2553

[ci skip]

Fix wording and appearance on build artifacts documentation



See merge request !2550

[ci skip]

Add image to 2fa security documentation



See merge request !2549

[ci skip]

Refactor commits API documentation

Blocked by https://gitlab.com/gitlab-org/gitlab-ce/issues/10960 which needs to be fixed or documented.

Closes #4217 

See merge request !2465

[ci skip]

Fix a missing letter in the documentation.

Hello,

I just found a missing letter in the PHP CI configuration documentation. This MR allow to fix that 😄 

See merge request !2519

Fix MR diff 'Edit' button

It now works and has the right size.

See merge request !2542

More highlighted diff fixes

See merge request !2545

Fix grammar and typos in file finder docs



See merge request !2547

[ci skip]

Make sure non-highlighted diffs are still escaped

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/12521

See merge request !2544

Remove user from groups when they are removed from LDAP

Fixes #159 

Currently, we only update user permissions if they come back from LDAP
as a valid user. I refactored some things in the `access.rb` file so we
update permissions no matter what. Now the user is removed from groups
and admin access is revoked, in addition to the previous behavior of
blocking the user.

See merge request !124

File finder can be invoked from anywhere!



See merge request !2543

Add support for ZIP build artifacts for Pages

This is based on https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/116

It adds support for creating pages from zip archives.

Omnibus change: https://gitlab.com/gitlab-org/omnibus-gitlab/issues/1057

See merge request !117

[ci skip]

Add method to calculate total size of artifacts in subpath

See merge request !2500

Diff highlight themes

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/12484

See merge request !2530