Pass variables from deployment project services to CI runner

## What does this MR do?

This commit introduces the concept of deployment variables - variables
that are collected from deployment services and passed to CI runner
during a deployment build.
Deployment services specify the variables by overriding
"predefined_variables" method.

This commit also configures variables for KubernetesService

## Why was this MR needed?

We need these values for https://gitlab.com/gitlab-org/gitlab-ce/issues/23580

## Does this MR meet the acceptance criteria?

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

Refers to https://gitlab.com/gitlab-org/gitlab-ce/issues/23580

See merge request !8107

Resolve "Add a doorkeeper scope suitable for authentication"

## What does this MR do?

- Add a single new scope (in addition to the `api` scope we've had) - `read_user`
- Allow creating OAuth applications and Personal access tokens with a scope selected
- Enforce scopes in the API

## What are the relevant issue numbers?

- Closes #20492 
- EE counterpart for this MR: gitlab-org/gitlab-ee!946

See merge request !5951

Resolve "Manual actions on pipeline graph"

## What does this MR do?
Improves the pipeline graph:
- add actions to each node
- always show the status icon
- improves style
- adds new icons to use only on the pipeline graph
- fixes tooltip body
- adds partial to render the graph node

### Hover state:
@dimitrieh 

This MR does not implements 100% of the mockups - https://gitlab-org.gitlab.io/gitlab-design/progress/dimitrie/pipelines-graphic/22604-spec-previews/#artboard0

As you can see in the mockups, each node has 2 separate hover states, one for the all content and one for the action icon.
In order to not hover the all content when we hover the action icon we would need to refactor the all HTML & CSS of all the pipeline graph, lines included.
The hover problem can be seen in the following video.
[video](https://drive.google.com/file/d/0B2xW80W4hUf0cnJoS1RGQ2hWZlU/view)

As you can see in the video, the build node is hovered even when the mouse seems to be far from the element.

It does not seem wise to me to change the HTML & CSS now for two reasons:
- we would need to rewrite almost everything;
- we will probably rewrite everything when we move this to vue.

Given the latter point, and considering it will be a bug effort to make the hover states equal to the mockups, I suggest we do that when we rewrite the all view.
This is fixable, though, but requires some effort & time.

I can, although, be missing something. @annabeldunstone do you see any quick/easy fix here?


## Screenshots (if relevant)
[video](https://drive.google.com/file/d/0B2xW80W4hUf0OFhZaXlKTW5mS3c/view?usp=sharing)

![Screen_Shot_2016-12-12_at_12.38.25](/uploads/8f015b0d476c832912e1530208f3d70d/Screen_Shot_2016-12-12_at_12.38.25.png)
![Screen_Shot_2016-12-12_at_12.38.31](/uploads/51de435f1120142d9683f06854d66507/Screen_Shot_2016-12-12_at_12.38.31.png)
![Screen_Shot_2016-12-12_at_12.38.39](/uploads/642e7348bcf46a03d13d8eac1cb7ce6b/Screen_Shot_2016-12-12_at_12.38.39.png)
![Screen_Shot_2016-12-12_at_12.40.00](/uploads/781743893bc14cf05f4b8f258e2b58ba/Screen_Shot_2016-12-12_at_12.40.00.png)


Tooltip before
![Screen_Shot_2016-12-06_at_11.29.54](/uploads/b16c0434981a89fb68c4c053c2f1d6e6/Screen_Shot_2016-12-06_at_11.29.54.png)
Tooltip after
![Screen_Shot_2016-12-06_at_11.56.03](/uploads/e5e0ede0f3f8a5434e98373ab8a72500/Screen_Shot_2016-12-06_at_11.56.03.png)


## Does this MR meet the acceptance criteria?
- [x] [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
  - [x] Added for this feature/bug
  - [ ] 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?
Closes #22604


See merge request !7931

Ensure issuable state changes only fire webhooks once

Webhooks were fired twice when issuables were reopened or closed. Once for the status change and once for the `update` operation

Closes #25339

See merge request !8101

Shorten line length of issues and mrs

Limits container width on issue and mr pages. Shortens line length to human readable length.

![Screen_Shot_2016-12-02_at_12.48.08_PM](https://gitlab.com/gitlab-org/gitlab-ce/uploads/740647c0fd6ea4f0f0aef62155992afe/Screen_Shot_2016-12-05_at_12.54.12_PM.png)

Closes #20916 
Closes #24408

See merge request !7858

Add GitLab host to 2FA QR and manual info

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/25545

See merge request !6941

Added KaTeX license and procedure to build it for Gitlab

## What does this MR do?
Adds KaTeX license and the procedure for building KaTeX for gitlab. 

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

## Why was this MR needed?
Requested by @stanhu

## Screenshots (if relevant)
Not relevant. 

## Does this MR meet the acceptance criteria?

- [X] [Changelog entry](https://docs.gitlab.com/ce/development/changelog.html) added
- [X] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [X] API support added
- Tests
  - [X] 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 !8132

The two factor authentication account string only had the user's
email address. This led to ambiguous entries in two factor
code generating apps. This adds the GitLab host to the account
string in the standard format (according to Google). No matter
the code generator this change disambiguates the entry.

Mattermost Notifications Service

## What does this MR do?
closes #22269 

## Screenshots 

![mattermost](/uploads/de71c121f544a91305b6dfa6dc4c5738/mattermost.png)  
![slack](/uploads/081d75d49239319d94332abda214fb98/slack.png)

## Does this MR meet the acceptance criteria?

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


See merge request !7764

Fix 8.15 RC1 requires quite amount of downtime

See https://gitlab.com/gitlab-org/gitlab-ce/issues/25635

See merge request !8106

Update grape to 0.18.0

## What does this MR do?

Update grape to 0.18.0. Required for the settings API.

## What are the relevant issue numbers?

#22928

See merge request !8057

Fix specs in Ruby 2.1

Ruby 2.1 requires a basename argument to `Tempfile.open`, so just call
it something that makes sense in context for the spec.

See merge request !8138

Replace static fixture for abuse_reports_spec

## What does this MR do?

Replace static HAML fixture for `abuse_reports_spec` by dynamically created one.

## What are the relevant issue numbers?

#24753

See merge request !7644

This commit introduces the concept of deployment variables - variables
that are collected from deployment services and passed to CI runner
during a deployment build.
Deployment services specify the variables by overriding
"predefined_variables" method.

This commit also configures variables for KubernetesService

Add missing group policy spec

See merge request !8122

Made Ci::Builds to have same ref as Ci::Pipeline in dev fixtures

See merge request !8110

Update custom hooks docs and set 4.1.0

See merge request !8040

Ruby 2.1 requires a basename argument to `Tempfile.open`, so just call
it something that makes sense in context for the spec.

UX Guide: add guidance on cursor usage

Add guidance to the UX guide on when to use what mouse cursor.

See merge request !8128

If we leave this as a regular migration, we could have the following flow:

1. Application knows nothing about scopes.
2. First migration runs, all existing personal access tokens have `api` scope
3. Application still knows nothing about scopes.
4. Second migration runs, all tokens created after this point have no scope
5. Application still knows nothing about scopes.
6. Tokens created at this time _should have the API scope, but instead have no scope_
7. Application code is reloaded, application knows about scopes
8. Tokens created after this point only have no scope if the user deliberately
   chooses to have no scopes.

Point #6 is the problem here. To avoid this, we move the second migration to a
"post" migration, which runs after the application code is deployed/reloaded.

`valid_api_token?` is a better name. Scopes are just (potentially) one facet of
a "valid" token.

- Previously, AccessTokenValidationService was a module, and all its  public
methods accepted a token. It makes sense to convert it to a class which accepts
a token during initialization.

- Also rename the `sufficient_scope?` method to `include_any_scope?`

- Based on feedback from @rymai

- The `scopes_form` partial can be used in the `admin/applications` view
  as well

- Don't allow partials to access instance variables directly. Instead, pass
  in the instance variables as local variables, and use `local_assigns.fetch`
  to assert that the variables are passed in as expected.

- Change a few instances of `render :partial` to `render`

- Remove an instance of `required: false` in a view, since this is the default

- Inline many instances of a local variable (`ip = 'ip'`) in `auth_spec`

Split the existing feature spec into both feature and controller specs.
Feature specs assert on browser DOM, and controller specs assert on database
state.

- Use whitespace to separate the setup, expectation and teardown phases.

- Based on @dbalexandre's review
- Extract token validity conditions into two separate methods, for
  personal access tokens and OAuth tokens.

- The list of scopes that's displayed while creating a personal access
  token is identical to the list that's displayed while creating an OAuth
  application. Extract these into a partial.

- The list of scopes that's displayed while in the show page for an OAuth token
  in the profile settings and admin settings are identical. Extract these into
  a partial.

- Mainly whitespace changes.

- Require the migration adding the `scope` column to the
  `personal_access_tokens` table to have downtime, since API calls will
  fail if the new code is in place, but the migration hasn't run.

- Minor refactoring - load `@scopes` in a `before_action`, since we're
  doing it in three different places.

- This module is used for git-over-http, as well as JWT.

- The only valid scope here is `api`, currently.