* Add back option to bundle CUDA kernel binaries with builds.
* Disable runtime CUDA kernel compilation on Windows, couldn't get this working,
since it seems to depend on visual studio being installed, even though for
this particular case it shouldn't be needed. CMake only at the moment.
* Runtime compilation on linux/mac should now work if nvcc is not installed in
the default location, but available in PATH.
* Disable precompiled cuda binaries, always do at run time
* Change preview samples default to 10
* Hide volume panels since they don't do anything yet
* OpenCL now only uses GPU/Accelerator devices, it's only confusing if CPU
device is used, easy to enable in the code for debugging.
* OpenCL kernel binaries are now cached for faster startup after the first
time compiling.
* CUDA kernels can now be compiled and cached at runtime if the CUDA toolkit
is installed. This means that even if the build does not have CUDA enabled,
it's still possible to use it as long as you install the toolkit.