Support for shaders with LUTs.
Shaders: Add HQx shader.
GameView: Reset pixel store parameters and unbind texture after saving the state texture.

Leaving these parameters in place will result in unexpected behaviour later.
Add updated xBR LV2 multi-pass shaders.
OEMultipassShader: Remove quotes around numbers.
Work around strange CG shader bug.

These lines should actually be equivalent, fixes HQx and xBR shaders.
OEGameView: Lock context while loading LUT textures.
Merge pull request #1535 from Armada651/shaders

Add HQx and xBR shaders and LUT textures