PROPOSAL: AMY should handle MIDI in and out

[bwhitman]

Since we have AMY handling a real time sequencer, we should also allow it to parse and handle MIDI messages, so that we reduce note on latency to 0. This would mean wiring up AMY to the MIDI hardware on a device and having APIs that allow for note stealing, etc.

This could be unnecessary if we find a way to get Python to respond in a predictable amount of time. We can try this out on AMYboard.