Blender Git Loki

- couldn't help myself, got distracted working on something else and
wondered what these silly data pointers in MDeformVert were for.
Turns out they aren't even need! Just taking up extra memory and
space and confusing the armature deform algorithm. Naturally I
had to clean things up. Sorry Ton.

Deform weights are still stored in a pretty expensive and unnecessary
way, probably use about twice as much memory as needed, and do
way too many memory allocs.
- moved armature_deform_verts into armature.c
- some python code accessed the MDeformWeight data pointers, but
did so in a completely wrong way, I am positive this code could
never have worked (or maybe things changed during tons refactor),
regardless it wouldn't work now... will test later.