Fix race condition with UpdateMirrorWorker Lease

Any time we modify the project import state to an in progress we're going to execute the sidekiq job not lease to try to obtain in this workflow. This fixes the UI problem when an user try to update a mirror just inside a lease timeout.

Closes #748 

See merge request !641

Run Sidekiq in inline mode for Elastic Search related specs



See merge request !652

Run Sidekiq in inline mode to ensure indexing occurs in spec



See merge request !651

Update changelog



See merge request !649

[ES] Improved code search

Changelog item is already there

See merge request !648

CE upstream

@ayufan Please resolve conflicts:

```
Unmerged paths:
  (use "git add/rm <file>..." as appropriate to mark resolution)

	deleted by them: app/services/create_commit_builds_service.rb
	both modified:   app/services/git_push_service.rb
	both modified:   app/services/git_tag_push_service.rb
	both modified:   spec/models/ci/pipeline_spec.rb
	both modified:   spec/requests/ci/api/builds_spec.rb
```

@ayufan Assigned to you since you are the author https://gitlab.com/gitlab-org/gitlab-ce/commit/39203f1adfc6fee3eca50f0cab99ffc597865200

/cc @jacobvosmaer-gitlab 

See merge request !644

The format of the `config/resque.yml.example` file has changed and we
need to adjust the reading of the connection URL.

Update ruby 2.3.1

We where using 2.3.0, now 2.3.1

cc @connorshea 

See merge request !5790

Resolve "Format branch, tag, and commit in environment list"

## What does this MR do?
Updates Environments page rows to match the new pipeline updates

## Are there points in the code the reviewer needs to double check?
I removed `private` from `avatars_helper.rb` so I could use `user_avatar`.

## What are the relevant issue numbers?
Closes #20059 

## Screenshots (if relevant)
![Screen_Shot_2016-08-08_at_11.44.36_AM](/uploads/62fbb475a7d9cc613fe5ba1715229553/Screen_Shot_2016-08-08_at_11.44.36_AM.png)
![Screen_Shot_2016-08-08_at_11.44.41_AM](/uploads/ce1bd3ab62c0bc8091e9b6f85012ed36/Screen_Shot_2016-08-08_at_11.44.41_AM.png)



See merge request !5687

[Fix] Push rules check existing commits in some cases

Closes https://gitlab.com/gitlab-org/gitlab-ee/issues/815

See merge request !640

Instrument Project.visible_to_user

## What does this MR do?

This MR instruments `Project.visible_to_user`

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

No.

## Why was this MR needed?

The method in question was not instrumented due to being a Rails scope.

## What are the relevant issue numbers?

#12425

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added
- Tests
  - [ ] All builds are passing
- [x] 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 !5793

Improve pipeline processing

## What does this MR do?
This works on top of https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5295 trying to solve some edge cases introduced by that Merge Request. The fix switches to a state machine which is already a part of `Ci::Pipeline` and uses events with conditional transitions to switch between pipeline states.

This is approach is much more bullet proof and much easier to understand than a previous one where we were calling a `reload_status!` which manually updated `status`. Previous approach become confusing and prone to number of errors.

## Why was this MR needed?
This improves changes introduced by https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5295

## What are the relevant issue numbers?
None, yet.

## Screenshots (if relevant)
Not needed.

## Does this MR meet the acceptance criteria?

- [x] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added (not needed since changelog for https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/5295 is already introduced)
- [ ] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [x] API support added (not needed)
- Tests
  - [x] Added for this feature/bug (most of tests do cover the triggering of Pipeline)
  - [ ] 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)
- [ ] [Squashed related commits together](https://git-scm.com/book/en/Git-Tools-Rewriting-History#Squashing-Commits)

See merge request !5782

Because this method is a Rails scope we have to instrument it manually
as regular the instrumentation methods only instrument methods defined
directly on a Class or Module.