Textures no longer appear in function declaration when not needed
remove texture definition when not used
remove duplicated function
Protect multiline macro function definitions

unprotected macro functions are incompatible with inline "if (use_opencl) MACRO_FCT()" ...
finish removing unused textures from kernels calls
revert src/gpu/initialize_gpu.c to original state
fix compilation bugs (cudacc stricter than gccwq)
removed white spaces
Adds initilization for backward trace arrays