Improve Geo documentation for 8.13

This merge-request was initiated after feedback from costumers about our documentation.

It's a bunch of small fixes to add extra troubleshooting and improve the understanding of the required steps.

# Documentation changes/added:

- [x] Add "Host key verification" troubleshooting doc for Geo
- [x] Update rsync instructions to preserve repository user/group ownership
- [x] Communicate better the setup steps and the correct order they must happen

cc @dewetblomerus @marin

See merge request !766

Add a trigger variable to docs trigger job

From https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/7089

See merge request !819

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

We have separate methods to delete redundant CE/EE access levels. So,
either `delete_redundant_access_levels` or
`delete_redundant_ee_access_levels` needs to be called, not both (as was
the case here).

Lines were duplicated.

Fix branch protection API

- EE-specific (spec) changes related to gitlab-org/gitlab-ce!6215.
- Related to gitlab-org/gitlab-ce#21513.

See merge request !718

Hides multiple board actions if user doesnt have permissions

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/23678

See merge request !816

As we now expire all caches and then call build_cache, we have to mock this in the spec as we are never creating an actual repo in the filesystem.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/23678

Fix for Elasticsearch::Transport::Transport::Errors::BadRequest: [400]

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/21036

See merge request !818

If you attempt to move an issue from one project to another and leave
labels blank, LabelsFinder would assign all labels in the new project
to that issue. The issue is that :title is passed along to the Finder,
but since it appears empty no filtering is done. As a result, all
labels in the group are returned. This fix handles that case.

Closes #23668

Enable SpaceAfterVariableColon in scss-lint

## What does this MR do?
Enables `SpaceAfterVariableColon` in `.scss-lint.yml`

## Are there points in the code the reviewer needs to double check?
None

## Why was this MR needed?
Improve SCSS maintainability and consistency

## Screenshots (if relevant)
None

## Does this MR meet the acceptance criteria?

- Tests
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [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 it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
#23485

See merge request !7080

Enable SpaceAroundOperator in scss-lint

## What does this MR do?
Enables `SpaceAroundOperator` in .`scss-lint.yml`

## Are there points in the code the reviewer needs to double check?
None

## Why was this MR needed?
Improve SCSS maintainability and consistency

## Screenshots (if relevant)
None

## Does this MR meet the acceptance criteria?

- Tests
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [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 it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
#23485

See merge request !7078

Enable trailingWhitespace in scss-lint

## What does this MR do?
Enables `trailingWhitespace` in `.scss-lint.yml`

## Are there points in the code the reviewer needs to double check?
None

## Why was this MR needed?
Improve SCSS maintainability and consistency

## Screenshots (if relevant)
None

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG.md) entry added
- Tests
  - [x] All builds are passing
- [x] Conform by the [merge request performance guides](http://docs.gitlab.com/ce/development/merge_request_performance_guidelines.html)
- [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 it does - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

## What are the relevant issue numbers?
#23485 

See merge request !7077

Fix pipeline graph hidden on commit and mr pages

## What does this MR do?

Dynamically invokes `new gl.Pipelines();` when an MR `builds` tab is clicked.

Dispatches `new gl.Pipelines();` on a `commit#builds` page.

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

## Why was this MR needed?

The pipeline graph was hidden on commit and mr pages

## Screenshots (if relevant)

Commit page:
![Screen_Shot_2016-10-14_at_18.16.18](/uploads/ee11dea0825d1489dc167292e16c8f41/Screen_Shot_2016-10-14_at_18.16.18.png)

MR:
![Screen_Shot_2016-10-14_at_18.16.39](/uploads/602c2fce2397c799bedb757bfd3010af/Screen_Shot_2016-10-14_at_18.16.39.png)

## Does this MR meet the acceptance criteria?

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

## What are the relevant issue numbers?


Closes #23325

See merge request !6895

Resolve "Build sidebar has extra space on Firefox"

## What does this MR do?

Accounts for the deprecated use of `document.body.scrollTop` on FF that was breaking the `translateSidebar` method.

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

## Why was this MR needed?

## Screenshots (if relevant)

![2016-10-22_23.16.31](/uploads/496810a9bb4fa4c3762023ff175572cb/2016-10-22_23.16.31.gif)

## Does this MR meet the acceptance criteria?

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

## What are the relevant issue numbers?


Closes #23665

See merge request !7060

invoked the pipelines class when builds are dynamically loaded and dispatched for commit builds page