squash! added several greens analysis and fixing bits to pyvq.betas
squash! added several greens analysis and fixing bits to pyvq.betas

splitting pyvq.betas.{greens function tools} to new module and class in greens.py... and adding greens.py module

kwschultz/vq,markyoder/vq,markyoder/vq,kwschultz/vq,markyoder/vq,kwschultz/vq