- No-one seems to remember why we are building with /MT
- The thread local vars causing race conditions  which is a blocking issue for supporting USD on windows.
- We have to ship the CRT libraries anyhow for python.
- Intels TBB allocator doesn't like /MT
This patch moves blender over to /MD and moves building of the deps to VS2017 including an new lib folder (win64_vc15) so it should cause minimal disturbance.
Passes the unit tests in both release and debug builds with the same pass-rate as the MT build (one failing test in debug on both builds)
- yaml-cpp needed a version bump to 0.6.3 build with vs2017
- OpenCollada needed a similar fix (pull #610) but that hasn't merged in nearly a year so i added it to our patch
- Both openVDB and OpenColorIO needed a preprocessor define otherwise they defaulted to a dllimport interface which was a warning for the /MT build but a straight up build error with /MD