Improve BitBucket integration documentation [ci skip]

This MR will improve the BitBucket integration documentation by

- mentioning the need to reconfigure GitLab after changing the configuration file, if you're using the omnibus package.
- adding a section about configuring a Host entry for bitbucket.org.
- switching additional steps 1 and 2, because connecting to BitBucket will only work after you added the SSH key and the Host entry.
- using sudo for the ssh connection in step 2, so that it is more obvious, that the git account should be used to establish the connection.

See merge request !670

Order commit comments in API chronologically

When fetching commit comments via API, the comments were not ordered,
but just returned in the order Postgresql finds them. Now the API always
returns comments in chronological order.

Same as !628 but with CI

See merge request !768

CI script: remove directives with default value

See merge request !1841

Remove Guard

None of the GitLab B.V. developers were using it.

See internal https://dev.gitlab.org/gitlab/gitlabhq/issues/2360

See merge request !764

Fix upgrader script

This is a fix for upgrader script not guessing the latest version correctly.

Upgrader now handles versions where a version part (major/minor/patch) can have multi-digit number, also ensures that the latest version is chosen from git tags by converting tag to Gitlab::VersionInfo and than selecting the latest/greatest version.

Fixes: #1476

See merge request !695

Make namespace API available to all users

### What does this MR do?

This MR makes it possible for a user to query namespaces to which he/she has access. Also, it adds documentation for the existing API.

### Why was this MR needed?

Even though the `groups` API exists, it might still be useful to have an endpoint that tells the namespace type (e.g. `user` vs. `group`), especially if a user has access to a number of different projects.

### What are the relevant issue numbers?

Closes https://github.com/gitlabhq/gitlabhq/issues/9328

See merge request !708

Use entity number for plus sign in push emails

Was doing some testing today and found that both outlook and gmail had issues displaying the html content produced for push emails when a file was added.

This is how gmail shows it:
![Gmail_name](https://gitlab.com/stevenorman/gitlab-ce/uploads/24be115dbae97997bc02e2ec70d9870c/Gmail_name.png)

And this is for Outlook:
![Outlook_name](https://gitlab.com/stevenorman/gitlab-ce/uploads/4b5a54956139d36d78f9c61c83e99928/Outlook_name.png)

iOS devices work with the + entity, as does Mail on OS X, but I'm wondering if it is only available for newer html parsers (a quick browse on the w3c site seems to show that it was added in html 5).

Changing the entity to `+` and both gmail and outlook and iOS and Mail.

See merge request !721

Omit link to generate labels if user does not have access to create them

On a project that has no labels, a user was provided a link to create labels on the "Labels" tab, resulting in a 404. This MR changes the next to "No labels created" if the user lands on this page but does not have permission to add a label.

Screenshot:

![image](https://gitlab.com/stanhu/gitlab-ce/uploads/cb04659cf3a0abe1e072cb78d0964b94/image.png)

Closes https://github.com/gitlabhq/gitlabhq/issues/8353

See merge request !752

Refactor CI script
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

cc @valery

See merge request !1840

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Trigger hooks create on backup restore

Number of users migrating from installation from source to omnibus get this issue. This can be fixed with a bash one liner but we already have a script that creates hooks in gitlab-shell. Added to gitlab:shell:install task call to `bin/create-hooks`. This script is idempotent which means it will only rewrite hooks if something changed.

Fixes https://dev.gitlab.org/gitlab/gitlabhq/issues/2208, https://github.com/gitlabhq/gitlabhq/issues/9101 and for the most part https://github.com/gitlabhq/gitlabhq/issues/8161

See merge request !762

Added autogenerated .gitlab-ci.yml

See merge request !1839

Remove show actions from Admin and Project DeployKeys

Example styling after:

> ![Screen_Shot_2015-06-03_at_6.04.51_PM](https://gitlab.com/gitlab-org/gitlab-ce/uploads/105801a7e390224066721bba200c4909/Screen_Shot_2015-06-03_at_6.04.51_PM.png)

Closes #1741

See merge request !763

None of the GitLab B.V. developers were using it.

Also style all key fingerprints consistently across the app.

Add 2FA docs

See merge request !757

Group improvements

* remove projects before removing group
* execute all hooks/events from project destroy when group removed
* log group create/remove
* delay remove of namespace directory (to prevent NFS issues)

Inspired by !759

See merge request !761

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Remove gitlab:env:check task.

Rake task that checks for git user git settings is a leftover from early days.

It is not being used by the web editor(and web editor is also being redone atm) so this rake task just causes confusion.

Adresses internal issue https://dev.gitlab.org/gitlab/gitlabhq/issues/2362

See merge request !758

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Conflicts:
	spec/features/projects_spec.rb

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Conflicts:
	spec/features/projects_spec.rb

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>