Fixing use of UT_String tokenizer
Updating GU_CortexPrimitive

Added missing virtual functions, removing deprecated functions, handling changes in GU_ConvertParms, and GU_Primitive factory create signature
Adding friendship with bindings for access to private constructor.

I was never really sure why this wasn't required before, but I guess a gcc 4.4 is a bit pickier
Fixing FromHoudiniGroupConverter tests to account for difference in default attributes
Including SYS_Types to avoid compile issue in H13.0.256
Fixing IMG_DeepShadow interface changes
Using new IMG_DeepPixelWriter