Add feature flag for Dependency Scanning reports parsing

See merge request gitlab-org/gitlab-ee!8760

Add milestones autocomplete for epics

Closes #5603

See merge request gitlab-org/gitlab-ee!8632

Allow public forks to be deduplicated

See merge request gitlab-org/gitlab-ee!8696

As discussed in:
https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/23508#note_123296899

Snapshotting doesn't use git, and will miss the required shared data.

When a project is forked, the new repository used to be a deep copy of everything
stored on disk by leveraging `git clone`. This works well, and makes isolation
between repository easy. However, the clone is at the start 100% the same as the
origin repository. And in the case of the objects in the object directory, this
is almost always going to be a lot of duplication.

Object Pools are a way to create a third repository that essentially only exists
for its 'objects' subdirectory. This third repository's object directory will be
set as alternate location for objects. This means that in the case an object is
missing in the local repository, git will look in another location. This other
location is the object pool repository.

When Git performs garbage collection, it's smart enough to check the
alternate location. When objects are duplicated, it will allow git to
throw one copy away. This copy is on the local repository, where to pool
remains as is.

These pools have an origin location, which for now will always be a
repository that itself is not a fork. When the root of a fork network is
forked by a user, the fork still clones the full repository. Async, the
pool repository will be created.

Either one of these processes can be done earlier than the other. To
handle this race condition, the Join ObjectPool operation is
idempotent. Given its idempotent, we can schedule it twice, with the
same effect.

To accommodate the holding of state two migrations have been added.
1. Added a state column to the pool_repositories column. This column is
managed by the state machine, allowing for hooks on transitions.
2. pool_repositories now has a source_project_id. This column in
convenient to have for multiple reasons: it has a unique index allowing
the database to handle race conditions when creating a new record. Also,
it's nice to know who the host is. As that's a short link to the fork
networks root.

Object pools are only available for public project, which use hashed
storage and when forking from the root of the fork network. (That is,
the project being forked from itself isn't a fork)

In this commit message I use both ObjectPool and Pool repositories,
which are alike, but different from each other. ObjectPool refers to
whatever is on the disk stored and managed by Gitaly. PoolRepository is
the record in the database.

Port "Further improvements to Project overview UI" to EE

See merge request gitlab-org/gitlab-ee!8552

Web Terminal FE

See merge request gitlab-org/gitlab-ee!8732

[EE] Remove RemoveOldWebHookLogsWorker

See merge request gitlab-org/gitlab-ee!8751

Revert "Add instance-level maven endpoint for download"

See merge request gitlab-org/gitlab-ee!8756

Fix ability to choose shards for selective sync

See merge request gitlab-org/gitlab-ee!8717

Fix transaction pollution in Shard.by_name (EE)

See merge request gitlab-org/gitlab-ee!8755

Resolve "Add subscription table to GitLab.com billing areas"

Closes #7772

See merge request gitlab-org/gitlab-ee!7885

Documentation for "`only/except: merge-requests` for merge request pipelines"

See merge request gitlab-org/gitlab-ee!8652

This reverts commit d2f55f9a.

Show closed epics in roadmap

Closes #8035

See merge request gitlab-org/gitlab-ee!8658

Remove spec from smoke tests.

See merge request gitlab-org/gitlab-ee!8749

Remove Sidekiq::Testing in RepositoryController spec

Closes #8757

See merge request gitlab-org/gitlab-ee!8752

[EE] Use FastDestroy for deleting uploads

See merge request gitlab-org/gitlab-ee!8589

Encrypt CI/CD builds tokens / EE

See merge request gitlab-org/gitlab-ee!8750

Add package name to dependency scanning reports

See merge request gitlab-org/gitlab-ee!8694

Brings back 1e8f1de0 reverted in !23644

Closes #52342

See merge request gitlab-org/gitlab-ce!23436

Resolve "Group Security Dashboard metrics MVC"

See merge request gitlab-org/gitlab-ee!8631

EE: Documentation for Group-level Kubernetes cluster configuration

See merge request gitlab-org/gitlab-ee!8719

CE upstream - 2018-12-06 10:22 UTC

See merge request gitlab-org/gitlab-ee!8724

This reverts commit 1e8f1de0, reversing
changes made to 62d97112.