OpenCL is supported by CMake OCCT solution
3rdparty directory is changed to <occt root>
3rdparty seeking in additional places if 3rdparty dir isn't defined
Test for exceptions corrected to handle FPE when built with with SSE2 option on Windows (NumericError raised instead of specific exceptions)
New test for performance of bspline intersections added
sse2 added; build bitness hardlinked to compiler
"bitness" variable was hidden