Align avatar and commit content within commit row

## What does this MR do?
Aligns the user avatar on `Compare`

## What are the relevant issue numbers?
Closes #18787 

## Screenshots (if relevant)
<img src="/uploads/9525a599989f6a9faca54d9f9c62f755/Screen_Shot_2016-06-20_at_11.25.08_AM.png" width="800px">
<img src="/uploads/6c96ed629f377d69745548309006a520/Screen_Shot_2016-06-20_at_11.25.19_AM.png" width="800px">


See merge request !4764

Fixed issue with notification dropdown not updating active

## What does this MR do?

This fixes an issue where the notification dropdown wouldn't correctly update the selected notification type in the dropdown. I've also added a spinner to show the action is happening & removed the flash message for success.

## What are the relevant issue numbers?

Closes #18480 

## Screenshots (if relevant)

![notifications](/uploads/5ed5055d180c12450cea77543ae5f44e/notifications.gif)

See merge request !4615

Optimize Banzai::Filter::RelativeLinkFilter

See merge request !4813

Updated blank state for environments and deployments

## What does this MR do?

Adds a designed blank state to environments and deployments.

@markpundsack do we want to hide the new environments when empty? Looks weird otherwise with the green button at the top.

## What are the relevant issue numbers?

Closes #18661 

## Screenshots (if relevant)

![Screen_Shot_2016-06-21_at_09.55.03](/uploads/cf768aba3fd85a596d24b7be4fe6a6c0/Screen_Shot_2016-06-21_at_09.55.03.png)

![Screen_Shot_2016-06-21_at_09.55.10](/uploads/b7b7dba90b613cfa867b084661b36b06/Screen_Shot_2016-06-21_at_09.55.10.png)

See merge request !4818

Resolve "Tooltip for pinning sidebar"

## What does this MR do?
Adds tooltip to show whether sidebar is pinned/unpinned

## What are the relevant issue numbers?
Closes #18743 

## Screenshots (if relevant)
![Screen_Shot_2016-06-17_at_12.14.25_PM](/uploads/162f52084a770012cdc621122acd6c6c/Screen_Shot_2016-06-17_at_12.14.25_PM.png)
![Screen_Shot_2016-06-17_at_12.14.35_PM](/uploads/d9296720aeada972441f48d9a3d2f7f8/Screen_Shot_2016-06-17_at_12.14.35_PM.png)

See merge request !4759

    A lot of git operations were being repeated, for example, to build a url
    you would ask if the path was a Tree, which would call a recursive routine
    in Gitlab::Git::Tree#where, then ask if the path was a Blob, which would
    call a recursive routine at Gitlab::Git::Blob#find, making reference to
    the same git objects several times. Now we call Rugged::Tree#path, which
    allows us to determine the type of the path in one pass.

    Some other minor improvement added, like saving commonly used references
    instead of calculating them each time.

Fix builds API response that did not include commit data

## What does this MR do?

This is fix for problem with builds API response not including information about commit this build is created for.

## What are the relevant issue numbers?

Closes #18476 

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry 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 [style guides](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CONTRIBUTING.md#style-guides)
- [x] Branch has no merge conflicts with `master` (if you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !4827

Show proper image ID on registry page

## What does this MR do?
Display the container registry image ID (from the config blob) instead of the first image layer ID

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

## Why was this MR needed?
To show proper image ID on container_registry page.
This only supports manifest V2, since the manifest V1 doesn't expose information about Image ID.

## What are the relevant issue numbers?
Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/18159.

## Screenshots (if relevant)
![Screen_Shot_2016-06-21_at_13.16.44](/uploads/db0d3ed8c8b90fafc8dbf1644c2354b0/Screen_Shot_2016-06-21_at_13.16.44.png)

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [x] Added for this feature/bug
  - [ ] All builds are passing
- [ ] 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 you do - rebase it please)
- [x] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !4821

Allow to fetch LFS from CI

## What does this MR do?

This adds support for fetching LFS object from CI jobs (mostly it's made for supporting GitLab CI).

## What is left?

- [x] Write tests covering a new authorization mechanism

cc @grzesiek @marin

See merge request !4465

Fix of on-hover state for 'Edit' button on tree view

It's already reviewed and merged to EE, so it's just a back-port.

See merge request !4823

Cache Participable#participants in instance variable

See merge request !4803

GitLab CI Yaml template dropdown

## What does this MR do?
Make it possible to select a dropdown for an easy start with GitLab CI.

## What are the relevant issue numbers?
Closes #17521

## TODO
- [ ] Backend
  - [x] CHANGELOG item
  - [x] Fix rubocop failure
  - [x] API Support
  - [x] New tests
  - [x] Add disclaimer to the top of the gitlab-ci.yml
- [ ] Frontend
  - [x] New tests

See merge request !4411

Make it possible to lock runner on a specific project

Make it possible to lock runner on a specific project.

![Screen_Shot_2016-06-20_at_4.03.08_PM](/uploads/186378643a20106ff0b67b6fd8bd7f28/Screen_Shot_2016-06-20_at_4.03.08_PM.png)

----

![Screen_Shot_2016-06-20_at_9.54.52_PM](/uploads/c479abdffaf19f383bb6b5a42bdd6cc3/Screen_Shot_2016-06-20_at_9.54.52_PM.png)

----

![Screen_Shot_2016-06-20_at_9.56.26_PM](/uploads/6ad838679b0c28a1fe2e20e9224387ea/Screen_Shot_2016-06-20_at_9.56.26_PM.png)

Closes #3407

See merge request !4093

Remove calls to Rugged::BranchCollection#each from extracts_path before_action

See merge request !4802

Remove explicit Gitlab::Metrics.action assignments, are already automatic.

See merge request !4731

Closes #18661

https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4093#note_12594802