improved discrete stitching
Merge branch 'devel' of https://github.com/embree/embree into devel
parallel_for_for working
added iterator concept to scene
parallel_for partitiones equally amoung threads
added regression test for parallel_for
updates to parallel_for_for
added parallel_for_for_prefix_sum
moved parallel_for_for_prefix_sum to separate file
Merge branch 'devel' of https://github.com/embree/embree into devel