[Bf-python] Vertex Influence for no-armatured objs

[Patrick]

Hmm, I would have it be on object and have it return one of these two 
things:

an NMesh object that has been trimmed down to only contain the points in 
the group(s), or
a list of vertex indexes that you can access in the mesh

Building it off of NMesh seems to be the wrong way to go around it if 
the vertex groups are in the object.

Further however, I think it would make the most sense for the vertex 
groups to be stored in the mesh.  Surely this would require some major 
refactoring though, but if you have two bone setups, with different 
meshes, and you want to make switch the mesh on one of them to the same 
mesh as the other one, the vertex groups don't follow correctly.  If you 
want to do this, you have to copy the mesh over and reparent it and 
ajust it so it fits on the bones.  Not really a big deal (Hasn't come up 
for me), but it seems kind of confusing to me.

But thats probably a much bigger change.