also update modplug for util/math refactor
DN-MC6000MK2: Initial revision
DN-MC6000MK2: Map some controls and the VU meter LEDs directly
DN-MC6000MK2: Looping

- Loops: Manual, beat and beatroll
- Censor: Use reverseroll instead of reverse
- Scratching: Don't modify keylock mode
DN-MC6000MK2: Track loading

- Solo cue mix when loading a track (can also triggered manually
  by pressing Shift + Cue Mix)
- Slip mode fixes (still does not always work as expected)
Fix compile errors in m4a decoder
DN-MC6000MK2: Samplers and various improvements

- 16 samplers (4 per deck)
- Hotcue fixes
- Sync mode switching improvements
- Use cue mix LEDs as track load indicator
- Delete obsolete filter controls
DN-MC6000MK2: Polishing

- Global shift state
- Slip mode fixes
- Looping improvements
- Cue button controls AutoDJ fade/skip
- Shift + play triggers stutter play
- Internal refactoring of hotcues
- Delete obsolete constants & triggers