v3.20.12 - The DLS Update

Full Changelog: v3.16.5...fbf0e14

• Added DLS Support:
  • play DLS files!
  • play RMIDI with embedded DLS!
  • convert DLS to SF2 with accurate precision!
• Added MIDI Builder: create MIDI Files from scratch!
• Changed soundfont to GeneralUserGS
• Fixed volume envelope decay and hold times
• Fixed XG Bugs
• Added Nearest Neighbor interpolation (disabled by default)
• Fixed RMI exporting
• UI Updates