Chord progression computation
Perhaps this is the conflict resolve!
Dealt with db bottlenecks.
Merge branch 'master' of https://github.com/Natalybr/ProgTag

Conflicts:
	prog_tag/musicapp/machine_learning/ml.py
	prog_tag/musicapp/machine_learning/ml_algorithms_test.py
	prog_tag/musicapp/models.pyc