[Bf-committers] Use DerivedMesh instead of Mesh in GeometryExporter

[Daniel Tavares]

Hey Nathan,

These are the changes I made in the GeometryExporter so it uses DerivedMesh
as opposed to Mesh. It still needs work, or possibly, not as many changes as
are in there. But given this is my first attempt at changing Blender's code,
I want to get some feedback, before I go to deep in this rabbit hole.

http://codereview.appspot.com/4387052/


Cheers,

Daniel (dBugSlayer)