Test Suite for Rectangle class

See http://pipwerks.com/journal/2009/02/18/fun-with-canvas-and-mootools-a-rectangle-class/ for an explanation of this page.

Tested in: Firefox 3 (OSX & WinXP), Safari 3 (OSX), Opera 9.6 (OSX), IE6 (WinXP), and IE7 (Vista).

Known issues: IE (VML via excanvas.js) doesn't support gradient strokes.