transform bitmaps

changed order of vertices/texture coordinates.

Change-Id: I35bd8026aa091bf05f1cb54a735aa235a3cd1480
cleanup, unify shaders/renderHelper

Change-Id: Ib9062728ad2ccf0921d4fd04db43189a10fc7c5c
unify transmitted texture coordinate name

Change-Id: I8c45ffeb6eb62ebe4d08214cccaaad6237621276
gradients

move gradients from spritedevicehelper to renderHelper,
render them with shaders.

Change-Id: Id1b7c2d435e15d0e5f12ca32e7fe7311301a705b
use gradients in canvashelper

Change-Id: I242f63bb055336d208dad5efced3618c9f89e47f