Other improvements:
- Ensure slash commands autocomplete doesn't break when noteable_type is not given
- Slash commands: improve autocomplete behavior and /due command
- We don't display slash commands for note edit forms.
- Add tests for reply by email with slash commands
- Be sure to execute slash commands after the note creation in Notes::CreateService
Signed-off-by: Rémy Coutable <remy@rymai.me>

Signed-off-by: Rémy Coutable <remy@rymai.me>

Also, pass options as instance variables, making the DSL more
user-friendly / natural.
Signed-off-by: Rémy Coutable <remy@rymai.me>

- Return only slash commands that make sense for the current noteable
- Allow slash commands decription to be dynamic

Other improvements:

- Add permission checks in slash commands definition
- Use IssuesFinder and MergeRequestsFinder
- Use next if instead of a unless block, and use splat operator instead of flatten
Signed-off-by: Rémy Coutable <remy@rymai.me>

The first one is /cc
Signed-off-by: Rémy Coutable <remy@rymai.me>

Improve slash command descriptions, support /due tomorrow
Signed-off-by: Rémy Coutable <remy@rymai.me>

Signed-off-by: Rémy Coutable <remy@rymai.me>

Check for update_issuable permission in Notes::SlashCommandsService
Signed-off-by: Rémy Coutable <remy@rymai.me>

Signed-off-by: Rémy Coutable <remy@rymai.me>

Some important things to note:

- commands are removed from noteable.description / note.note
- commands are translated to params so that they are treated as normal
  params in noteable Creation services
- the logic is not in the models but in the Creation services, which is
  the right place for advanced logic that has nothing to do with what
  models should be responsible of!
- UI/JS needs to be updated to handle notes which consist of commands
  only
- the `/merge` command is not handled yet

Other improvements:

- Don't process commands in commit notes and display a flash is note is only commands
- Add autocomplete for slash commands
- Add description and params to slash command DSL methods
- Ensure replying by email with a commands-only note works
- Use :subscription_event instead of calling noteable.subscribe
- Support :todo_event in IssuableBaseService
Signed-off-by: Rémy Coutable <remy@rymai.me>

Fix bug where destroying a namespace would not always destroy projects
    
There is a race condition in DestroyGroupService now that projects are deleted asynchronously:
    
1. User attempts to delete group
2. DestroyGroupService iterates through all projects and schedules a Sidekiq job to delete each Project
3. DestroyGroupService destroys the Group, leaving all its projects without a namespace
4. Projects::DestroyService runs later but the can?(current_user,
    :remove_project) is `false` because the user no longer has permission to
    destroy projects with no namespace.
5. This leaves the project in pending_delete state with no namespace/group.
 
Projects without a namespace or group also adds another problem: it's not possible to destroy the container registry tags, since `container_registry_path_with_namespace` is the wrong value.

The fix is to destroy the group asynchronously and run `execute` directly on Projects::DestroyService.
 
Closes #17893

See merge request !4341

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

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.

Corrected links/usernames in performance guide

## What does this MR do?

This fixes two broken links in the performance guide and removes the mention of Josh as he no longer works for GitLab.

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

No.

## Why was this MR needed?

The guide contained two broken links, and Josh no longer works for GitLab.

## What are the relevant issue numbers?

None.

## Does this MR meet the acceptance criteria?

- [x] [Documentation created/updated](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/doc/development/doc_styleguide.md)
- [ ] 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 !5772

Remove unused SpamReport model; this was renamed to SpamLog

See merge request !5778

There is a race condition in DestroyGroupService now that projects are deleted asynchronously:

1. User attempts to delete group
2. DestroyGroupService iterates through all projects and schedules a Sidekiq job to delete each Project
3. DestroyGroupService destroys the Group, leaving all its projects without a namespace
4. Projects::DestroyService runs later but the can?(current_user,
   :remove_project) is `false` because the user no longer has permission to
   destroy projects with no namespace.
5. This leaves the project in pending_delete state with no namespace/group.

Projects without a namespace or group also adds another problem: it's not possible to destroy the container
registry tags, since container_registry_path_with_namespace is the wrong value.

The fix is to destroy the group asynchronously and to run execute directly on Projects::DestroyService.

Closes #17893

Resolve "New pipeline auto-completion"

## What does this MR do?

Add auto-completion to new pipeline.

## What are the relevant issue numbers?

Closes #19725 

See merge request !5389