Update JSDoc.
Rename _cloning parameter to _preserve.
Merge Path.Rectangle and Path.RoundRectangle.
Various improvements to Color caching mechanisms.
Handle color transformation in Item#transform() rather than Path#_applyMatrix().

Fixes an issue with BoucingBalls.html, now that CompoundPath#applyMatrix is true.
Move #applyMatrix setting to PathItem.
Update BouncingBalls.html example.