splits one track into two tracks.
The first of the resulting tracks will contain
only meta events, while the second will
contain all other events.
Both tracks will be terminated with a MetaEndOfTrack
The first argument is a list that contains the MIDI
song descriptor of the source track and the track number
in that song.
The second argument is a similar list for the track where
meta events should go, and the third argument is a list
describing where the remaining events should go.
The MIDI song descriptors
should be values returned by either