Add SDKs.props that controls which version of OptiX and Cuda SKDs are used through OPTIX_USE_VER (x.x.x) and CUDA_USE_VER (x.x) environment variables
Fix SKDs.props import condition. Remove redefinition inherited dependency libs (kernel32.lib etc..)
Use CudaToolkitIncludeDir, CudaToolkitLibDir, CudaToolkitBinDir variables instead of manually deriving paths
To upper case optix version env variable name
Update readme.md