Pass `updated_at` to get only incremental changes since last update

Refine CI Statuses

## What does this MR do?

This MR introduces classes for each relevant CI status.

## What are the relevant issue numbers?

Closes #24273

See merge request !7889

Use `--extended-regexp` in lint-doc for compatibility with Darwin grep

Now it should work on all platforms.

See merge request !7943

GLM shorthand reference for projects from the same namespace

Closes #21679

See merge request !7255

Authorize users into imported GitLab project

https://gitlab.com/gitlab-com/support-forum/issues/1313

See merge request !7936

Fixed MR widget content wrapping for XS viewports

Centers the "Accept Merge Request" button within the MR widget (and adds a bit of right/left padding) for viewports smaller than 768px.

BEFORE:
![Screen_Shot_2016-12-02_at_8_53_01_AM](/uploads/fcdae5302a1407090483dd3cff868c51/Screen_Shot_2016-12-02_at_8_53_01_AM.png)

AFTER:
![Screen_Shot_2016-12-02_at_9_43_37_AM](/uploads/f7d1dce082b79d263f05cea3c90e870a/Screen_Shot_2016-12-02_at_9_43_37_AM.png)

cc: @markglenfletcher @annabeldunstone 
Closes #25202

See merge request !7900

Ensure state param has a valid value when filtering issuables.

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/25064

This fix makes sure we only call safe methods on issuable when filtering by state.

See merge request !2038

Document the public Project API and document `GET /projects/:id/users`

Documentation was not updated in !7843. Also the `GET /projects/:id/users` endpoint was not documented at all!

See merge request !7897

Remove unused errors css

`.error-page` isn't being used anywhere as far as I can see so I removed it

See merge request !7933

Remove unused votes.scss

`.votes-inline` isn't being used anywhere

See merge request !7934

NIGNX -> Nginx

This shouldn't be in all caps, and it should be spelled correctly!

See merge request !7929

It's secret variables, not secure

See merge request !7939

[ci skip]

Refactor CI variables docs

See merge request !7751

[ci skip]

Make the 'Group projects' links clickable in the admin screens

## What does this MR do?
This MR makes the group links within the 'users' section of the admin interface clickable. Currently, to view the details of groups a user is a member of, you have to go back to the 'groups' tab (which isn't ideal).

## Are there points in the code the reviewer needs to double check?
No

## Why was this MR needed?
It's a UX improvement - it saves going back to the 'groups' a user is a member of and then clicking the group to view the group details.

## Screenshots (if relevant)

### Before
![Screenshot_from_2016-11-21_14-25-01](/uploads/2a6b75efd4c700e5760c64f0db17e847/Screenshot_from_2016-11-21_14-25-01.png)

### After
![Screenshot_from_2016-11-21_14-24-42](/uploads/9be288c1d9e4cf818c96e11e24790860/Screenshot_from_2016-11-21_14-24-42.png)

## Does this MR meet the acceptance criteria?

- [ ] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) 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?

See merge request !7620

Document button secondary states

## What does this MR do?
Document the changes from #24145 and !7797.

It also updates the icons and color section in the basics page.

## Does this MR meet the acceptance criteria?

- [ ] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) 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?
#24145

cc @awhildy

See merge request !7924

Describe hover, focus and active states for primary and secondary
buttons.

Organized the icons section in a table. Replaced images for icons
so they are all the same size.

Organized the color section in a table. Replaced the images with
new ones so the table would have a more manageable size. Updated
the values for some colors to show the $color-light shade.

Remove commented sections

Remove `db/schema.rb`

Add db/schema.rb from origin/master

Fix typos

Added element extensions spec for .matches and .closest

## What does this MR do?

Adds tests for `Element.prototype.matches` and `Element.prototype.closest`.

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

## Why was this MR needed?

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [ ] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) 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?

See merge request !7755

Refactor create service spec

## What does this MR do?
Use let instead instance variables to cache create user operation.

Union some example into one.

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

## Why was this MR needed?
Time before: 1 minute 11.81 seconds

Time after: 52.47 seconds

- [x] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- n/a [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- n/a API support added
- Tests
  - n/a Added for this feature/bug
  - [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?

See merge request !7609