Distorted Android

Tesselate DistortedBitmaps better - now all the triangles long edges point at the center of the bitmap, which makes z-distortions look much better!

Merge remote-tracking branch 'origin/master'

Cull back faces of triangles.

Minor stuff - make the Bitmaps and the Cubes agree on the size of the grid, mostly.

Fix for Bug #16: When rotated at an angle, surfaces get increasingly transparent.

This also fixes the saturation, chroma, alpha + contrast effects, while completely breaking macroblocks :)

Fix for Bug #21: implement z-shear.

Fix for Bug #18: DISTORT effect: disappearing triangles

Fix for Bug 19: SWIRL effect: mess if Center out of Region.

beginnings of support for drawing the Region in Vertex3D app.

Minor stuff - comments.