Blender Git Loki

First round of code review requests by Campbell

Merge branch 'master' into soc-2013-paint

Conflicts:
source/blender/blenloader/intern/versioning_270.c

UI tweaks:

Make texpaint UI look less like a spaceship!

Thanks to so3Datel again!

Fix Scons compilation

Of course it would help if I added the -actual- data files as well

The rest of the new icon set by Pawel Lyczkowski for the mask and fill
tools in the paint branch.

Merge branch 'master' into soc-2013-paint

Conflicts:
source/blender/editors/sculpt_paint/paint_image_proj.c
source/blender/editors/sculpt_paint/paint_utils.c

Add missing mask display support from subsurf.

* Add custom color for new layers.

This is not ideal because of the internal representation of byte images,
which is straight alpha. This means that on the display we will get an
opaque color if we try painting on a transparent image. To bypass this I
have enforced alpha to be 1 in that case. If we are to support this we
should upload byte images as premultiplied meaning we take a performance
hit...hmmmm...no.

* Add dependency update when painting on image editor. Should handle
update of layer icons nicely

Code cleanup: use sets

Brush Color tidy-up.

Nice UI mockup from so3Datel on blendeartists

Fix style after old bad merge

Fix some clamping issues.

Stencil eye candy (but can be useful too):

Allow setting the mask viewport color.

Mask brush:

* On painting, enable stencil
* Stencil checkbox forces redraw.

Bump blender subversion.

Merge branch 'master' into soc-2013-paint

Mask brush implementation:

* Users can now select/create a mask brush to directly interact with the
stencil. This acts similarly to a paint brush, however only the mask
texture is relevant and the brush uses a Mask value to paint.

* Also, now inverted mask layer is correctly displayed.

Fix possible crash:

Could happen if user changes UV layer name from the mesh data properties
and has that uv layer assigned to a material slot.
In that case UV layer name is invalid and we could end up without UV
layers for drawing/painting.
Just reuse default UV layer in that case.

Support for drawing the stencil layer in the viewport.

This should give much better preview of which part is paintable.
Unfortunately only supported in blender internal for now.