Blender Git Loki

=Python Bugfix=
The python wrapper code for shape keys was really bad; whoever wrote it
(mis)read the wrong section of blender's codebase and got the totally wrong
idea. The code was definitely broken to the point where either it had to be
fixed for 2.45, or else the entire keyblock wrapper would have to be removed
from the stable branch. The fact that it didn't crash is just sheer luck;
the code assume mesh keys were MVerts, when in fact mesh keys are just
arrays of three-float vectors.

So shapekey data can now be editing directly, and is exposed as Mathutils.Vectors.
Also I updated the epydocs to explain how it all works now.