[ci skip]

Fixes gitlab-org/gitlab-ce#27674

Allows to use slash command /target_branch <target_branch_name> in merge requests notes and description.
Command allows to specify target branch for current merge request.

Proposed in #23619

Allow rendering of PlantUML diagrams in Markdown documents using fenced blocks:

    ```plantuml
    Bob -> Sara : Hello
    Sara -> Bob : Go away
    ```

Closes: #4048

As per this comment
https://gitlab.com/gitlab-com/support/issues/374#note_22056587 we're
moving documentation around from the support workflows.

Signed-off-by: NRémy Coutable <remy@rymai.me>

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

* Regenerates tokens for all models that have them
* Remove variables, since they are basically just storing encrypted data
* Bumped version up to 0.1.6
* Updated related docs

Puts back trailing whitespace

Changes after review

Changes after review

Adds Changelog entry

Follow documentation styleguide

[ci skip] UX guide: clean up term tables in copy

[ci skip] UX guide: update dropdown max height for multiline items

It said `<slug>.review.example.com` at one place,
`review-<slug>.example.com` elsewhere, and no mention of `review`
at all in other places. We now leave out `review` everywhere.

The script will check some php.ini settings warn you if they
are set incorrectly, and then download the latest composer.phar
in the current directory. These lines will, in order:

- Download the installer SHA-384 to the current directory
- Download the installer to the current directory
- Verify the installer SHA-384 which you can also cross-check https://composer.github.io/pubkeys.html
- Run the installer
- Remove the installer & the installer SHA-384
Signed-off-by: NRémy Coutable <remy@rymai.me>

The documentation seemed to be out of date with
actual defaults in configuration and code. 

I wanted to practice GFM markdown, so I picked this page more or
less at random. I flattened out the text a little. It's not as
interesting, but will be easier to translate. Use it if it looks
like an improvement. If not, at least I got some practice out of the deal!
Signed-off-by: NRémy Coutable <remy@rymai.me>

Signed-off-by: NRémy Coutable <remy@rymai.me>

This sends a project_update hook when a repo is updated.  This does not include
renaming or transferring a project.  Those are covered by project_rename and
project_transfer.  This will get called, however, when the visibility is
changed.

Also remove duplicate link in the index to that documentation