Fix for Tiling Sprites that use trimmed frames. Before they would use the trimmed frame size, rather than the actual frame size. This updates generateTilingTexture to resolve it.
Merge branch 'pixidev/dev'

Conflicts:
	src/pixi/extras/TilingSprite.js
Merge branch 'pixidev/dev'
Small documentation fix.
Fixed bug in gl.bindTexture which tried to use an undefined private var.
Merge pull request #579 from photonstorm/dev

Fix for Tiling Sprites that use trimmed frames.