Throughout sointu, we assume stereo audiobuffers, but were passing
around []float32. This had several issues, including len(buf)/2 and
numSamples*2 type of length conversion in many places. Also, it
caused one bug in a test case, causing it to succeed when it should
have not (the test had +-1 when it should have had +-2). This
refactoring makes it impossible to have odd length buffer issues.
The RPC and sync library mechanisms were removed for now; they never really worked and contained several obvious bugs. Need to consider if syncs are useful at all during the compose time, or just used during intro.
