[Bf-codereview] Normals baker from sculpt data (issue4518055)

[g.ulairi at gmail.com]

Reviewers: bf-codereview_blender.org,

Description:
Hi everybody!

Morten Mikkelsen and me were working under baker, which could bake
normals directly from mesh with multi-resolution modifier without using
much of additional memory.

Here's patch for Blender which makes able to bake in such way. It isn't
replacing existing maker, just adds new method which could be specified
from UI and bakes against given subdivision level.

It's my first change in baker-related area, so i want this patch be
reviewed by other developers.

Thanks!

Please review this at http://codereview.appspot.com/4518055/

Affected files:
   release/scripts/startup/bl_ui/properties_render.py
   source/blender/blenkernel/BKE_multires.h
   source/blender/blenkernel/intern/customdata.c
   source/blender/blenkernel/intern/multires.c
   source/blender/blenlib/BLI_math_geom.h
   source/blender/blenlib/intern/math_geom.c
   source/blender/editors/object/object_bake.c
   source/blender/makesdna/DNA_scene_types.h
   source/blender/makesrna/intern/rna_scene.c