Blender Git Loki

Bevel Tool Cut-Off Method: Mostly working implementation

This is the first implementation of the cut-off vertex mesh method which
just creates an N-gon at the end of each profile. There are a few items that
need to be finished, but the structure is working/complete:
1. The direction and length from the boundary vertices to the cut-off faces'
corner vertices.
2. Representative "example" faces for the new ngons.