cmake fix: -static intel now added in quotes
added subdiv split heuristic to bvh4hair builder
Merge branch 'master' into devel
some cleanups in bvh4hair builder
added 3level pre-subdivision stage to bvh4hair builder
Merge branch 'devel' of https://github.com/embree/embree into devel
increased allocated memory in bvh4hair builder to make presubdivision work
bugfixed in spatial split