added Flagbearer to Antibirth soundtrack

-updated shuffling so now instead of checking through the entire list of soundtracks against the 'ban' list every time you shuffle, it constructs a list of every allowed soundtrack and checks from that when shuffling (faster, more efficient and less likely to have problems)
-fixed bug where shuffling while only having 1 soundtrack enabled for shuffle would make the game crash

-fixed bug with selecting 'default' for sfx jingles in custom mode
-added option for sfx jingles to be disabled for specific soundtracks
-stopped the ascent music getting mixed up if you had set shuffle on new floor

added support for sfx jingles

added checks for if a soundtrack has downpour set but not dross and if mines but no ashpit and mausoleum but no gehenna

-added extra integration with jukebox
-couple small bugfixes