GRAPHICS: Add OpenGL extension registry
GRAPHICS: Only use packed depth-stencil framebuffer if extensions allow it
ANDROID: Use extensions to query NPoT textures
ANDROID: Remove force_redraw
BUILD: Add ENABLE_TOUCH feature
ANDROID: Move Touch controls to TouchControlsBackend
ANDROID: Move grim touch controls to engines/grim
ANDROID: Toggle run when 20% of height is crossed
MISC: Remove OSystem kFeatureVirtControls
ANDROID: Remove KeyReceiver interface