This reverts merge request !1877

This reverts merge request !2380

Ability to control the output of account/pleroma/relationship in statuses in order to improve the rendering performance.
See `[:extensions, output_relationships_in_statuses_by_default]` setting and `with_relationships` param.

FollowingRelationship storage & performance optimizations (state turned `ecto_enum`-driven integer, reorganized indices etc.).

Every time someone tries to use it, it goes mad and tries to scrape the
entire fediverse for no visible reason, it's better to just remove it
than continue shipping it in it's current state.

idea acked by lain and feld on irc

Closes #1595 #1422

Related: pleroma/pleroma#1616

Some of the actions used to have a user map as a subject, which was then
changed to an array of user maps. However instead of migrating old data
there was just a hack to transform it every time, moreover this hack
didn't include all possible actions, which resulted in crashes. This
commit fixes the crashes by introducing a proper database migration for old data.

Closes #1606

This reverts merge request !2274

Once more, with feeling

- Removed Grouped Reports; API needs proper architecture/refactor
- Cannot set Tesla adapter in AdminFE as it's not safe yet
- Layout/rendering improvements