This patch switches from boost's filesystem v2 to v3.
This should be completely smooth due to filesystem v3 is pretty
old already.
Patch by Sven-Hendrik Haase (aka svenstaro), thanks!
Some drivers don't support passing include paths with spaces in them, nor does
the opencl spec specify anything about how to quote/escape such paths, so for
now we just resolved #includes ourselves. Alternative would have been to use c
preprocessor, but this also resolves all #ifdefs, which we do not want.
* Fix missing update when editing objects with emission materials.
* Fix preview pass rendering set to 1 not showing full resolution.
* Fix CUDA runtime compiling failing due to missing cache directory.
* Use settings from first render layer for visibility and material override.
And a bunch of incomplete and still disabled code mostly related to closure
sampling.
* 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.
* Compute MD5 hash to deal with nvidia opencl compiler cache not recognizing
changes in #included files, makes it possible to do kernel compile only
once and remember it for the next time blender is started.
* Kernel tweak to compile with ATI/linux. Enabling any more functionality than
simple clay render still chokes the compiler though, without a specific error
message ..
