1.3 adds more music

A playtester noticed that one of my tracks was Bloody Tears from Castlevania. Apparently, someone uploaded their EDM remix of it under CC. That's obviously not legal. In an effort to find a replacement with a suitably generous license, I got carried away...

• Removed Bloody Tears from the song selection.
• Added 8 new tracks, bringing the total to 12, from 11 different artists.
  
  • 5 are under CC0, CC-BY, or CC BY-SA and on by default.
  • 5 are under CC BY-NC, and off by default to help avoid copyright strikes for streamers.
  • 2 more are off by default
• Can now turn off and on all tracks under a noncommercial license (should help streamers avoid streamer-unfriendly music)
• Pause menu now plays a preview of a song, if it's enabled (the currently playing song is shown in red)
• Music, graphics and scores are now saved across playthroughs. Personal bests show with green text.
• You can play as any character on your first playthrough with only one player.