Complete rewrite of ShapeTracer
Complete rewrite of ShapeTracer

As of this writing: every unit test passes. But visual inspection shows
some unit tests should be failing, so those need updating.

Also this class needs a little optimization (re Polygon usage)

But overall this feels like a much more theoretically sound approach
than the previous implementation.
mickleness/pumpernickel,mickleness/pumpernickel,mickleness/pumpernickel