BitmapData Quality Settings .drawWithQuality()

Adds support for changing the StageQuality setting used to render the
BitmapData when generting textures.

The default setting is StageQuality.BEST, however BEST is a relative
term since newer versions of the Flash Player have given us HIGH_8x8,
HIGH_8X8_LINEAR, HIGH_16x16, and HIGH_16X16_LINEAR.

Regarding Issue #39