Make stuck builds detection more performant

Closes #27523

See merge request !9025

Rename builds to jobs in the API

Closes #28515

See merge request !9463

GitLab should have an option to prevent users from signing in from multiple IPs

Closes #27520

See merge request !8998

removes redundant code from gitlab database file

See merge request !9282

Fix issues mentioned but not closed for JIRA

Closes #26028

See merge request !9687

Use gitlab-workhorse 1.4.0

See merge request !9724

Set max for Zen mode textarea to screen height

Closes #28704

See merge request !9667

Improve IssuableFinder performance

Closes #25503

See merge request !9030

Fixed spacing in mobile secondary nav

See merge request !9657

align schema.rb with upstream and fix rubocop warning about not freezing mutable constants and empty error classes

 + rename shared context

 - cleanup formating in haml
 - clarify time window is in seconds
 - cleanup straneous chunks in db/schema
 - rename count_uniqe_ips to update_and_return_ips_count
 - other

Remove "subscribed" field from API responses returning list of issues or merge requests

Closes #22374

See merge request !9661

Add gitaly server dependency

Closes gitaly#109

See merge request !9722

The `ReferenceExtractor` would return an array of `ExternalIssue`
objects, and then perform `Array#-` to remove the issues
closed. `ExternalIssue`s had `==` defined, but not `hash` or `eql?`,
which are used by `Array#-`.

Bug fixes, Gitaly gRPC support, experimental Redis integration.

The endpoint dropped, get ':id/repository/commits/:sha/jobs', should be
replace by a new endpoint.

[ci skip]

This commit was about 6 commits before squashing, with the main goal to
make all tests green. Now, after pushing this commit we'll see what the
CI has to say about that.

This commit only renames the commits, the cascading effects will be
dealt with later.

Fixes gitlab-org/gitlab-ce#28515

[ci skip]

Improve pipeline triggers API

See merge request !9713

In GitLab 9.0.0 we want to turn on Gitaly in Omnibus installations.
Gitaly is not a required component yet for source installations
because we want to iterate on the configuration and architecture some
more. Omnibus installations will have the option to completely disable
Gitaly if they want to or if necessary.

The new GITALY_SERVER_VERSION file which version of the Gitaly server
application is needed by the current GitLab version.