Fix #616: Fixed inconsistencies in subsonic error responses

Closes #616

See merge request funkwhale/funkwhale!467

Resolve "Document keyboard shortcuts"

Closes #611

See merge request funkwhale/funkwhale!465

Fix #606: Refresh profile after user settings update to avoid cache issues

Closes #606

See merge request funkwhale/funkwhale!464

Resolve "Add `Audience` field in AP representations when library is public"

Closes #553

See merge request funkwhale/funkwhale!463

Fix #597: Ensure admin links in sidebar are displayed for users with relavant…

Closes #597

See merge request funkwhale/funkwhale!462

Fix #597: Ensure admin links in sidebar are displayed for users with relavant permissions, and only them

Fix #598: Allow opus file upload

Closes #598

See merge request funkwhale/funkwhale!461

Fix #599: wrong album/track count on artist page

Closes #599

See merge request funkwhale/funkwhale!460

Fix #600: Removed "Activity" page, since all the data is available on the "Browse" page

Closes #600

See merge request funkwhale/funkwhale!459

Fix #272 and #586

Closes #272 and #586

See merge request funkwhale/funkwhale!458

Implement more subsonic endpoints

See merge request funkwhale/funkwhale!457

Fix #573: Added "type: funkwhale" and "funkwhale-version" in Subsonic responses

Closes #573

See merge request funkwhale/funkwhale!456

Fixed #581: missing track count on various library cards

Closes #581

See merge request funkwhale/funkwhale!455