Some cleanup and rearrangement to make the next set of features cleaner and
easier to implement...
Initial re-arranging of the UI to support the new envelopes...
Drop the automation envelope stuff into pydaw.py...  None of it's wired
up or remotely working yet, but it is present in the UI now....
Getting the song level CC editors more in line with how the rest of PyDAW
works.
Wrapping up work on envelopes