Feedback from:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3363#note_12669123

Which would return the email address for creating a new issue
by sending an email to that particular address.

So that we don't have to pretend that CreateNoteHandler
could handle a nil mail_key. Also, since NilClass#=~ would
just return nil for any regular expression, we could just
match it without checking nilness.

Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3363#note_12566407

Feedback:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3363#note_12566374

Feedback from:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3363#note_12420487

* master: (1246 commits)
  Update CHANGELOG
  Update tests to make it work with Turbolinks approach
  Use Turbolink instead of ajax
  Reinitialize checkboxes to toggle event bindings
  Turn off handlers before binding events
  Removed console.log Uses outerWidth instead of width
  Revert "Added API endpoint for Sidekiq Metrics"
  Added API endpoint for Sidekiq Metrics
  Added CHANGELOG entry for allocations Gem/name fix
  Filter out classes without names in the sampler
  Update the allocations Gem to 1.0.5
  Put all sidebar icons in fixed width container
  Instrument private/protected methods
  Fix Ci::Build#artifacts_expire_in= when assigning invalid duration
  Fix grammar and syntax
  Update CI API docs
  UI and copywriting improvements
  Factorize members mails into a new Emails::Members module
  Factorize access request routes into a new :access_requestable route concern
  Factorize #request_access and #approve_access_request  into a new AccessRequestActions controller concern
  ...

Don't fail builds for projects that are deleted when they are stuck

## What does this MR do?

Solves when dropping stuck connection.
```
Dropping stuck pending build 1545510 for runner 
NoMethodError: undefined method `origin_merge_requests' for nil:NilClass
    from /opt/gitlab/embedded/service/gitlab-rails/app/services/merge_requests/base_service.rb:50:in `merge_request_from'
    from /opt/gitlab/embedded/service/gitlab-rails/app/services/merge_requests/base_service.rb:57:in `each_merge_request'
    from /opt/gitlab/embedded/service/gitlab-rails/app/services/merge_requests/add_todo_when_build_fails_service.rb:5:in `execute'
    from /opt/gitlab/embedded/service/gitlab-rails/lib/gitlab/metrics/instrumentation.rb:164:in `execute'
    from /opt/gitlab/embedded/service/gitlab-rails/app/models/commit_status.rb:51:in `block (2 levels) in <class:CommitStatus>'
    from /opt/gitlab/embedded/service/gem/ruby/2.1.0/gems/state_machines-0.4.0/lib/state_machines/eval_helpers.rb:79:in `call'
...
```

This happens, because that `default_scope` of `Projects` filters returns the projects that are not deleted, where `Ci::Build` doesn't take into account.


See merge request !4609

Fix typo in obtaining a backtrace from all threads in gdb



See merge request !4612

Fix note polling when a window has been hidden

`refresh` was called, `refreshing` was set to true, but then because
`document.hidden` was true, `getContent` was never called, and
`refreshing` never got reset to `false`, which stopped polling entirely
until refresh.

See merge request !4635

Manually create todo for issuable

## What does this MR do?

Adds a button to the sidebar in issues & merge requests to allow users to manually create a todo item themselves.

## What are the relevant issue numbers?

Closes #15045 

## Screenshots (if relevant)

![Screen_Shot_2016-06-07_at_09.52.14](/uploads/00af70244c0589d19f241c3e85f3d63d/Screen_Shot_2016-06-07_at_09.52.14.png)

![Screen_Shot_2016-06-07_at_09.52.06](/uploads/e232b02208613a4a50cff4d1e6f119ff/Screen_Shot_2016-06-07_at_09.52.06.png)

![Screen_Shot_2016-06-07_at_09.51.14](/uploads/f1d36435d49ab882538ae2252bec8086/Screen_Shot_2016-06-07_at_09.51.14.png)

See merge request !4502

Update CHANGELOG

## What does this MR do?
Updates the CHANGELOG


See merge request !4549

Fixes bulk-assign labels not working when navigating through pages

## What does this MR do?
This MR fixes an issue on bulk-assign labels not working when navigating though pages. The functionality was not working because events on checkboxes weren't working. This re-runs `Issuable.initChecks()` and makes sure we are not leaving zombie event handlers by turning them off first.

Also fixes tests to use `wait_for_ajax` since label filtering is now using `Turbolinks` for redirection.

## 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
  - [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 !4632

Aligned the two navs horizontally

## What does this MR do?

Previously the 2 top navs were not aligned horizontally together. The top nav would be slightly to the left due to the settings dropdown. This corrects that by putting `position: absolute` on the dropdown toggle.

## What are the relevant issue numbers?

Closes #18513 

## Screenshots (if relevant)

![Screen_Shot_2016-06-13_at_10.20.22](/uploads/46f39a84dde74707578970f70ddda511/Screen_Shot_2016-06-13_at_10.20.22.png)

See merge request !4616

Update allocations Gem & ignore classes without names

## What does this MR do?

1. Updates the allocations Gem to 1.0.5 so it can be used on 2.2/2.3 without crashing
2. Changes the background sampler to ignore classes/modules without a name (as we can't do much with these)

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

No.

## Why was this MR needed?

Using MRI 2.2 or 2.3 would lead to a segmentation fault in the allocations Gem, sometimes this problem would also occur on 2.1

## What are the relevant issue numbers?

Not an issue, but the merge request that highlighted these problems: !3807

## Does this MR meet the acceptance criteria?

- [x] [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
  - [x] Added for this feature/bug
  - [ ] 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 !4645

Uses outerWidth instead of width

Revert "Added API endpoint for Sidekiq Metrics"

@DouweM please merge my accidental push to master.

See merge request !4651

This reverts commit 06e0ef07

We can't do a lot with classes without names as we can't filter by them,
have no idea where they come from, etc. As such it's best to just ignore
these.

This allows it to be used on Ruby 2.3 without it crashing all the time.