No need to fill a camera twice if not blending alpha

[FlixelCommunityBot]

Issue by moly from 2013-01-14T18:44:54Z
Originally opened as AdamAtomic#237

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This fix will fill the camera's buffer directly if alpha blending is not required, rather than filling the _fill bitmapData and then blitting that to the camera.

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moly included the following code: https://github.com/AdamAtomic/flixel/pull/237/commits

[IQAndreas]

Merged in c2fc664