Blender Git Loki

Added bevel regression test to tests.

Goes with companion files bevel_regression.blend
and mesh_ops_test.py just added to svn lib/tests/modeling.

Also changed the blender executable path for Apple case:
needed either 'Debug' or 'Release' in the path. I chose
'Debug', because not sure how to add otherwise. At any
rate, what was currently there didn't work at all.