this has the side effect of making some notes more accurate, the new
frequency= value in the test is closer to the true midi frequency of
830.609...Hz.
This works for me (tested playing midi to raw files on host computer, as
well as a variant of the nunchuk instrument on pygamer)
it has to re-factor how/when MIDI reading occurs, because reasons.
endorse new test results
.. and allow `-1` to specify a note with no sustain (plucked)
a waveform object (array of 'h') can be passed in, replacing the
standard square wave. This waveform must be a 'single cycle waveform'
and some obvious things to pass in are sine, triangle or sawtooth waves,
but you can construct whatever you like.
