Resolve "Configurable issue boards should be part of GitLab.com early adopter plan"

Closes #4115 and gitlab-com/support-forum#2729

See merge request gitlab-org/gitlab-ee!3497

Add example of finding the repmgr node id

Closes gitlab-org/build/team-tasks#46

See merge request gitlab-org/gitlab-ee!3491

Add example output for `repmgr standby setup`

Closes gitlab-org/build/team-tasks#36

See merge request gitlab-org/gitlab-ee!3501

Move ee-only files under top level ee directory

See merge request gitlab-org/gitlab-ee!3498

Tell the user what to prepare

Closes gitlab-org/build/team-tasks#61

See merge request gitlab-org/gitlab-ee!3494

It's useful to have sample output for this command, as it's a few moving
parts.

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Port from CE to EE: Changing OAuth lookup to be case insensitive

See merge request gitlab-org/gitlab-ee!3427

Update gitlab.yml.example to match the default settings for Geo sync workers

See merge request gitlab-org/gitlab-ee!3488

Copyedit Epics docs

Closes #4062

See merge request gitlab-org/gitlab-ee!3482

Rather than telling the user to read ahead to figure out what
information to prepare, tell them the variables we're going to make use
of, and link them back to where we described them.  This should help in
the case a user is skipping ahead.

Add notes about architecture to PG HA document

Closes omnibus-gitlab#2705

See merge request gitlab-org/gitlab-ee!3490

Fix in-progress repository syncs counting as failed

Closes #4053

See merge request gitlab-org/gitlab-ee!3424

Refactor cluster docs

See merge request gitlab-org/gitlab-ee!3486

Geo: Rename the old directory first when swapping out the recovered directory

Closes #4083

See merge request gitlab-org/gitlab-ee!3463

Geo: Ensure that LFS object deletions are communicated to the secondary

Closes #3962

See merge request gitlab-org/gitlab-ee!3481

Add geo hashed storage warning

See merge request gitlab-org/gitlab-ee!3480

Port of 38869-milestone to EE

See merge request gitlab-org/gitlab-ee!3484

Improve geo docs based on Sid demo

See merge request gitlab-org/gitlab-ee!3485

Disable file attachments for epics

Closes #3914

See merge request gitlab-org/gitlab-ee!3434

Remove upgraded licensed feature from list

See merge request gitlab-org/gitlab-ee!3477

Refactor  Cluster docs

Closes #39952

See merge request gitlab-org/gitlab-ce!15418

(cherry picked from commit d41e66cb)

644a2941 Add info about the installed apps in the Cluster docs
b7a01e08 Add info on creating your own k8s cluster from the cluster page
ee7ecc81 Add Ingress description from official docs
3b9773fc Change to Google Kubernetes Cluster and add internal links
bacf671a Move installation of apps higher

[EE] Update gRPC to v1.7.2

See merge request gitlab-org/gitlab-ee!3443

Geo - Move the primary node checkbox below the URL

See merge request gitlab-org/gitlab-ee!3483