Use data_source_exists? where possible instead of table_exists? in order to be Rails5 compatible

EE: Improve runner_type validations for Ci::Runner

See merge request gitlab-org/gitlab-ee!5672

EE: Resolve "A lot of constants redefinition warnings"

See merge request gitlab-org/gitlab-ee!5927

Add validation to webhook and service URLs to ensure they are not blocked because of SSRF

See merge request gitlab-org/gitlab-ee!5851

Truncate Geo event log with a delay

Closes #6221

See merge request gitlab-org/gitlab-ee!5897

Resolve "Strike through the whole line when vulnerability is dismissed"

Closes #6005

See merge request gitlab-org/gitlab-ee!5929

Docs: fix typo

See merge request gitlab-org/gitlab-ee!5931

Refactor LDAP docs

See merge request gitlab-org/gitlab-ee!3691

CE upstream - 2018-05-31 21:32 UTC

See merge request gitlab-org/gitlab-ee!5925

EE port of ide-jobs-list-components

See merge request gitlab-org/gitlab-ee!5904

Remove assign merge requests ability from reporter role

Closes gitlab-ce#44728

See merge request gitlab-org/gitlab-ee!5922

EE Port: Use NPM provided version of SortableJS

See merge request gitlab-org/gitlab-ee!5923

Which could extend from EE

* Replace `require` or `require_relative` with `require_dependency`
* Remove unneeded `autoload`

# Conflicts:
#	app/controllers/profiles_controller.rb
#	app/controllers/projects/issues_controller.rb
#	app/views/projects/issues/_nav_btns.html.haml
#	app/views/shared/issuable/form/_merge_params.html.haml
#	config/routes/project.rb
#	db/schema.rb
#	locale/gitlab.pot
#	spec/controllers/application_controller_spec.rb

[ci skip]

Update 404 and 403 pages

Closes #25955

See merge request gitlab-org/gitlab-ce!19096

Fix bootstrap squash checkbox alignment

Closes #47055

See merge request gitlab-org/gitlab-ce!19292

Fix bootstrap pipeline right alignment

Closes #46875

See merge request gitlab-org/gitlab-ce!19284

Resolve "Admin area > New Application form"

Closes #46817

See merge request gitlab-org/gitlab-ce!19290

Fix checkbox/radio button structure (EE)

See merge request gitlab-org/gitlab-ee!5913

Remove form-horizontal class where applicable

Closes #46744

See merge request gitlab-org/gitlab-ce!19262

Fix checkbox/radio button structure

Closes #46766 and #46719

See merge request gitlab-org/gitlab-ce!19254