Fix error 500 when sorting issues by milestone due date and filtering by labels

fixes #15557 

See merge request !4327

Add tooltips for common Event feed entries

This adds tooltips to the event target for events like "opened merge
request !XYZ"

After https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4090#note_11712839, several references in the event feed had titles but were still missing tooltips.

See merge request !4371

New style for close buttons

## What does this MR do?
Adds new style for all `Close` buttons

## What are the relevant issue numbers?
Closes #17756 
## Screenshots (if relevant)   
<img src="/uploads/a1d4cb8c22facb4c170e9cf3b4ae439a/Screen_Shot_2016-05-31_at_2.26.42_PM.png" width="800px">   
<img src="/uploads/d567694d79ec6bd5da0ff2faf8b262b0/Screen_Shot_2016-05-31_at_2.26.09_PM.png" width="800px">   
<img src="/uploads/f5e23d8031427079a334d4e03da466b0/Screen_Shot_2016-05-31_at_2.29.01_PM.png" width="800px">   


cc @dzaporozhets 


See merge request !4388

Upgrade Kaminari from 0.16.3 to 0.17.0.

Changelog: https://github.com/amatsuda/kaminari/blob/master/CHANGELOG.rdoc#0170

Deprecates `num_pages` in favor of `total_pages` and includes Rails 5 support.

Working towards #14286.

See merge request !4387

Create the specified remote directory during backup

This is idempotent, so there's no harm calling it if the directory
already exists.

Closes #12710

See merge request !4383

Changelog: https://github.com/amatsuda/kaminari/blob/master/CHANGELOG.rdoc#0170

Deprecates num_pages in favor of total_pages and includes Rails 5 support.

Confidential notes data leak

Fixes part of https://gitlab.com/gitlab-org/gitlab-ee/issues/575

See merge request !1967

Remove redundant factory namespace in build specs

Extracted from !4351.

See https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4351#note_12154604

See merge request !4373

Include Wiki attributes in Wiki page events webhook

The hook data we are sending is not 100% correct (we send details of the project, but should also send details of the "ProjectWiki" attributes like URLs and repositories relative to the wiki itself).

This is a follow up to #17506

Fixes #17507

See merge request !4138

This is idempotent, so there's no harm calling it if the directory
already exists.

Closes #12710

Remove project notification settings associated with deleted projects

On GitLab.com, there are 1560 project notification settings with no valid project all created on 2016-04-15 10:38:53 for some reason. This migration should purge
those entries.
    
b8f38437 should prevent this issue from occurring in the first place.
    
Closes gitlab-com/support-forum#678


See merge request !4311

On GitLab.com, there are 1560 project notification settings with no valid project
all created on 2016-04-15 10:38:53 for some reason. This migration should purge
those entries.

b8f38437 should prevent this issue from occurring in the first place.

Closes gitlab-com/support-forum#678

Add Application Setting to configure Container Registry token expire delay (default 5min)

This adds an option to configure Container Registry token expire delay. The default is set to 5mins (something that is also used by Docker Hub).

What is left:
* [x] Write test to check the expire_delay

Fixes: https://gitlab.com/gitlab-org/gitlab-ce/issues/17890

@stanhu I think that this should land in patch release of 8.8.

See merge request !4364

Added "wiki" section and removed "repository"

This is not needed when we specify a default.

Update docs: previous version is 8.7

The old version is 8.7.

See merge request !4288

Enable Wiki Page events from Webhook admin UI in a Project

* Added UI to enable page wiki events
* Documentation for this event in Webhooks page

Fixes #17506

--- 

![new_webhook_UI](/uploads/63ef24b4ccef13ac7a5fda83e9ce64ad/new_webhook_UI.png)

See merge request !4135

Conflicts:
	spec/models/build_spec.rb

Merge branch 'make-container-registry-authentication-service-compatible-with-older-docker' into 'master'

Make authentication service for Container Registry to be compatible with < Docker 1.11

This removes the usage of `offline_token` which is only present when using `Docker 1.11.x` instead we relay on `scope`. This should make it compatible with any client starting from 1.6 (I did test only 1.8 and up).

Right now we return 403 if unauthorized user doesn't have access to anything. In all other cases we return token, but with empty `access`, which simply disallow requested action.



See merge request !4363

This adds tooltips to the event target for events like "opened merge
request !XYZ"

Fix typo

Add missing "of" to CI YAML docs.

[ci skip]

See merge request !4331

Fix various documentation typos and spelling mistakes

[ci skip]

See merge request !4345

Add missing steps in update docs

Fixes #18009

[ci skip]

See merge request !4365