- added ability for ObjectPool’s constructor to accept either single classes or an array of classes that are randomly chosen from

- added new CanvasFilterRhythm class that makes filtering instances of BitmapCanvas easier

- created new ICanvas interface and two classes that implement it, SimpleCanvas and GridCanvas

- modified BitmapCanvas to use new ICanvas classes and added new setupLargeCanvas(scale:int) method

- added new CanvasPNGEncoder for creating PNGs from ICanvas classes

- added new ContextSavePNG – a simple class to assist in encoding and saving large PNGs from BitmapCanvas instances

- created two new BitmapCanvas examples, 06 and 07, to show new PNG encoding capabilities