Blender Git Loki

Fixes for smooth shading of primitves.

Reverses order of vertices that weld op gives to make ngon so that it doesn't
reverse the normal from what it used to be.
Fixed a bunch of inconsistent normals in primitives: circle (made normal(s)
point up instead of down), uvsphere, icosphere, cylinder, and cone.
Reviewed at http://codereview.appspot.com/4959056/.
Cone and Cylinder still don't shade properly with ngon end caps, but that is now a different issue from normals.