Blender Git Loki

Fix: Normal maps and triangulate modifier will give incorrect result on
rectangular faces after applying rotation, reported by Metalliandi

This issue is caused by floating point precision error. After applying
rotation, the edge lengths change slightly and on rectangular faces the
length comparison can be flipped. Solved by giving a slight offset to
the length calculation for the diagonal during triangulation
calculation. (Same as done during uv unwrapping)