Blender Git Loki

Sculpt: tool updates for latest changes

* Smooth: vert-face map is now only created when this tool is used, would be
best to also avoid using it here to avoid a sudden increase in memory, but
is not trivial.
* Grab: now no longer uses active verts list and loops over nodes like other
tools.
* Layer: uses original coordinates from undo now to save memory when not
using persistent layer.
* Anchored: this option works again now, though is still quite slow as it
loops over all verts/faces.

Smooth, layer tools and the anchored option could still be improved to use
less memory and/or work faster by only doing things per node.