Fix support for Python 3.5 in import script

Closes #1147 and #1148

See merge request !1129

See #1108: support using OAuth instead of JWT in front when logging in to a different domain

See merge request !1127

Support session/cookie based auth, see #1108

See merge request !1126

New theming system

See merge request !1125

Use scoped tokens to load <audio> urls instead of JWT

See merge request !1124

Increase image quality of downscaled images from 70 to 95

See merge request funkwhale/funkwhale!1112

Resolve "Removed masonry"

See merge request funkwhale/funkwhale!1123

Fix #1092: Ensure player doesn't disappear when last queue track is removed manually

See merge request funkwhale/funkwhale!1122

Fix #1078: Include tracks by album artist when filtering by artist on /api/v1/tracks

See merge request funkwhale/funkwhale!1121

Update followchannel.rst

See merge request funkwhale/funkwhale!1119

Build docker images for master branch

See merge request funkwhale/funkwhale!1118

Fix #1086: Added safeguard to ensure local uploads are never purged from cache

See merge request funkwhale/funkwhale!1116

Fix #1011: Ensure tracks linked to skipped upload can be pruned

See merge request funkwhale/funkwhale!1117

Fix #1087: Fix playlist modal only listing 50 first playlists

See merge request funkwhale/funkwhale!1115

Importer updates: watch directories, handle metadata updates

Closes #721 and #741

See merge request !1111