A javascript implementation of the Racket Drawing Toolkit.

Some functionality (notably fillRule) only works bleeding-edge browsers and nightlies, though the vast majority should work in any browser with decent Canvas support. IE9+, Safari 5+ and Chrome 20+ are pretty much required.

When browser support for the v5 Canvas API becomes widespread, a LOT of this code can be factored out. Specifically:
	- measureText
	- ellipse
	- arcTo
	- some of the Transformation pipeline stuff?
	- some of the Path stuff