Disable preloading

See merge request !502

Smaller CSS with purge CSS (130kb removed)

See merge request funkwhale/funkwhale!501

Fixed broken translations build

See merge request !500

Improve front-end performance

See merge request !499

Resolve ""Play Now" button doesn't queue properly"

Closes #632

See merge request funkwhale/funkwhale!498

Removed duplicated susbsonic tests

See merge request funkwhale/funkwhale!497

Fix #578: iframe embed

Closes #578

See merge request funkwhale/funkwhale!496

We were testing both xml and json rendering for every view but this takes a very long time, so we only do json for most views now.