Tracker timer algorithm changed

Redid the tracker algorithm to make life easier. The algorithm produces
a prescaler such that each tick represents a 64th note.

Also the user button changes the "scale" at which the sample notes are
played at. This is to support basic data compression similar to how
Stepmania compresses note charts (i.e., if the note only has quarter
beats, only four pieces of data are needed)
Bulk of the logic done

Got the communication handler done (need to make a GUI program to send
it data) and the music tracker that handles data.

Looks like the core logic of how this is works.
Major update

At the moment the MCU is now in a state that it'll tick at the accurate
BPM (as much as possible) and request more notes. However, at the moment
it's hard coded to 150 BPM until I can figure out the formula for other
speeds.

Uploading the debugging application used for testing. This also contains
a hard-coded chart for "V" from beatmania IIDX. The audio file is NOT
included due to copyright.