doc sync
fixed some wrong file headers
Merge branch 'v2.2' of https://github.com/embree/embree into v2.2
turning intersection filter on
enabling intersection filter by default but not in Xeon Phi
replacement for windows condition also in 2.2
merge from 2.2
Merge remote-tracking branch 'origin/v2.2'
improving hybrid perf under windows due to inlining
Merge branch 'master' of https://github.com/embree/embree
Merge remote-tracking branch 'origin/v2.2'