Fix auto-MR-close text from branch name

## What does this MR do?

Fix the MR-auto-close feature if a branch name begins with an issue IID.

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

It's one line, so check that line thoroughly :smiley:

## Why was this MR needed?

When I create a new MR from a branch starting with an issue IID, the description doesn't get suffixed with the 'Closes #blahblah' that it should do.

## What are the relevant issue numbers?

Don't think there are any.

## Screenshots (if relevant)

## Does this MR meet the acceptance criteria?

- [ ] [CHANGELOG](https://gitlab.com/gitlab-org/gitlab-ce/blob/master/CHANGELOG) entry added

See merge request !4836

Resolve "Destroying a project causes post_decline_request to be executed"

## What does this MR do?

Ensure we don't send "access request declined" to access requesters when a project is deleted.

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

I've created a service to decouple the notification sending from the AR model.

## Why was this MR needed?

Because there was an issue.

## What are the relevant issue numbers?

Fixes #18755, #18750.

## Does this MR meet the acceptance criteria?

- [x] No CHANGELOG needed.
- [x] 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 !4744

Rails's form helpers use the `$attr_before_type_cast` method where
available, and this value only appears to be updated on assignment, not
when the object is mutated in some other way:

    [1] pry(main)> mr = MergeRequest.new
    => #<MergeRequest:0x007fcf28395d88 ...>
    [2] pry(main)> mr.description = 'foo'
    => "foo"
    [3] pry(main)> mr.description << ' bar'
    => "foo bar"
    [4] pry(main)> mr.description
    => "foo bar"
    [5] pry(main)> mr.description_before_type_cast
    => "foo"
    [6] pry(main)> mr.description += ' bar'
    => "foo bar bar"
    [7] pry(main)> mr.description_before_type_cast
    => "foo bar bar"

* upstream/master: (353 commits)
  Put some admin settings in dropdown
  Add styleguide on configuration settings documentation
  Remove Duplicated keys add UNIQUE index to fingerprint
  Avoid autoload issue such as 'Mail::Parsers::AddressStruct'
  Move appearance settings as sub tab to application settings
  use rails root join
  fixed a couple of errors spotted in production
  Fix RangeError exceptions when referring to issues or merge requests outside of max database values
  Fix bug in `WikiLinkFilter`.
  Grammar and typographic changes to artifacts documentation
  Tweak grammar
  Small frontend code fixes and restore 8a2d88f commit
  Warn about admin privilege to disable GitHub Webhooks
  Listing GH Webhooks doesn't stop import process for non GH admin users
  fixup! updated docs for api endpoint award emoji
  Update CHANGELOG
  Ensure Todos counters doesn't count Todos for projects pending delete
  Add endpoints for award emoji on notes
  Sort API endpoints and implement feedback
  Add endpoints for Award Emoji
  ...

This is a try for a new approach to put the access checks at the service level.

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

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

This is to ensure we don't send unwanted notifications when deleting a
project. In other words, stop abusing AR callbacks and use services.

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

Implement custom notification level options

![Screen_Shot_2016-06-17_at_15.31.43](/uploads/3fc47d2f461b3e8b67bb8acaa304cf99/Screen_Shot_2016-06-17_at_15.31.43.png)

![Screenshot_from_2016-06-15_10-52-27](/uploads/88dbdd21d97e80ee772fe08fa0c9b393/Screenshot_from_2016-06-15_10-52-27.png)

part of #12758 

See merge request !4389

Cache todo counters (pending/done)

See merge request !4438