added test for offset distance. Very problematic to write test because of how reduce splits across extrema (makes output unpredictible) and because in certain cases such as cusps it isnt even possible to make segment simple if it starts where the derivative is zero.
added test for offset distance. Very problematic to write test because of how reduce splits across extrema (makes output unpredictible) and because in certain cases such as cusps it isnt even possible to make segment simple if it starts where the derivative is zero.

hfutrell/BezierKit,hfutrell/BezierKit