Merge pull request #478 from jeremygray/master

RatingScale 'hover' style
ENH: added unittools.degrees(radians)

also made many updates to psychopy.tools and psychopy.misc documentation
DOCS: tweaks
BF: python setup.py install was failing under win32

because post_install was not being included if built on a mac
TEST: polygon use the same window throughout

100% coverage of visual.helpers.pointInPolygon and .polygonsOverlap