* add new columns
* store local content ratings
* display and search content ratings
* add content_rating to search docs
* sync content rating from jellyfin, emby, plex
* force sync content rating for all libraries
* code cleanup
* use etags to optimize local movie scanner
* use etags to optimize local television scanner
* use etags to optimize local music video scanner
* code cleanup
* clean up genre, tag, studio orphans
* enforce foreign keys at connection level
* wip
* fix fragment scroll offset
* fix see all link for music videos
* add fake artist metadata
* not null artist id
* add artist scanning
* remove improperly named music videos
* code cleanup
* add artists to search results and collections
* clean up music video metadata / artist
* add artist view
* show music videos on artist page
* add music video artwork placeholder
* add music videos library
* add music video tables
* first pass at music video library scan
* support music videos in playouts
* display music videos in search results and collections
* fix music video thumbnails
* remove some obsolete fields