* fixed preprocessing in tccpp -> updated tccpp submodule
 * fixed processing order of user defined structs (structs are now sorted after parsing)
 * empty user defined structs are now removed completely (this messed up a lot of things before, including compiler crashes ...)
 * if there is no user defined transform output, don't read/create the primitives indices in the rasterization_program
 * transform_programs now define OCLRASTER_TRANSFORM_PROGRAM and rasterization_programs now define OCLRASTER_RASTERIZATION_PROGRAM (this allows one to have both programs in one file and simply #ifdef parts that are only available in one or the other)