[#413] fix parse mentions

See merge request pleroma/pleroma!577

Fix config.md path in README

See merge request pleroma/pleroma!581

Improve systemd service documentation

See merge request !580

Pleroma-API.md: Import from /wikis/Pleroma-only-api-endpoints

See merge request pleroma/pleroma!571

Use `systemctl` instead of `service` since it's not guaranteed the
latter will be on the system (e.g. Arch does not have it).

Add a way to use the admin api without a user.

See merge request pleroma/pleroma!576

Per-branch CI cache with force-recompilation of Pleroma

See merge request pleroma/pleroma!574

[#441] Fix characters converted to HTML being picked up by hashtag parser

See merge request pleroma/pleroma!575

Use "~" as a route namespace symbol on FE

See merge request pleroma/pleroma!530

update frontend

See merge request pleroma/pleroma!573

SetUserSessionIdPlugTest: try to fix random ci failures

See merge request pleroma/pleroma!570

Instance/Runtime static plug

See merge request pleroma/pleroma!567

This allows to set-up an arbitrary directory which overrides most of the
static files: index.html static/ emoji/ packs/ sounds/ images/ instance/
favicon.png.

If the files are not present in the directory, the bundled ones in
priv/static will be used.

2018 12 17 update frontend

See merge request pleroma/pleroma!565

Fix uploads test.

See merge request pleroma/pleroma!564

Fix update_profile failing due to OAuth token record in assigns instead of string

Closes #459

See merge request pleroma/pleroma!561

[#449] fix text field

See merge request pleroma/pleroma!563

Captcha

See merge request !550

Fix tagging problems for existing instances.

See merge request pleroma/pleroma!562

Add tests for Mix tasks

See merge request pleroma/pleroma!555