Huge conversion re-vamp.
Finished replacing color comparisons with the new assertColorMatch.
Lots of simplification and cleanup on color objects.
Huge re-work of delta e, conversions and tests for both.
Correcting py3-specific issue with color_diff matrix wrapper.
Cosmetic, but use Python floats instead of NumPy floats for the color_diff module. color_diff_matrix still uses NumPy floats, though.
Beginnings of Sphinx docs.
Preliminary doc work.