update frontend

See merge request !742

Use multiple hackney pools

See merge request !739

Use race condition free queries for following / unfollowing

See merge request !740

* federation (ap, salmon)
* media (rich media, media proxy)
* upload (uploader proxy)

Each "part" will stop fighting others ones -- a huge federation outbound
could before make the media proxy fail to checkout a connection in time.

splitted media and uploaded media for the good reason than an upload
pool will have all connections to the same host (the uploader upstream).
it also has a longer default retention period for connections.

docs/config.md: Fix syntax, pleroma_fe isn’t an atom

See merge request !738

docs/config.md: Fix typo, provide an example key with camelCase and where to find more

See merge request !737

[ci skip]

docs/Pleroma-API.md: Fix ex_doc title by changing the first h1 to it

See merge request !736

[ci skip]

follow request fixups

Closes #537

See merge request !734

New frontend configuration mechanism.

Closes #445

See merge request !700

activitypub: utils: update the state of *any* pending follow relationship that matches the actor and target

Rich Media support, part 2.

See merge request pleroma/pleroma!719

App list changes: Separate into two categories, and drop Subway Tooter.

See merge request !731

This is in preparation for 1.0. We'll be able to switch the config to the new
mechanism on PleromaFE then as well.

remove unnecessary filter (re !723)

See merge request !729

Correctly handle invalid credentials on auth login.

Closes #407

See merge request !728

Closes #407

Update the openrc service's retry with the correct format

See merge request !727