The test for intersection of two triangles sharing a common edge
has been optimized to reject non-overlaping triangles with
the least amount of exact arithmetics predicates.
Cherry pick of
d367762468
Fixing dep build script on Windows and removing some warnings.
Use bundled igl by default.
Not building with the dependency scripts if not explicitly stated. This way, it will stay in
Fix the libigl patch to include C source files in header only mode.
