Blender Git Loki

* Symmetry Feather option was not appearing
* Moved symmetry feather option to brush area of UI because it is a per-brush option
* Trunk has 'height' and my branch has 'layer_distance', height is way too generic and hard to search for, renamed this to 'layer_limit'
* Made layer limit and persistent base greyed-out if Layer is disabled
* Was getting warnings about gl_TexCoord being deprecated in GLSL version 1.30, so for now it is just gonna use the 1.00 version.

Why warn about deprecation when I explicitly asked for a version that still supports a feature? If I say 1.3, and 1.3 supports gl_TexCoord, then there is no problem with me using it. Kindly stfu compiler.

Deprecation makes people stupid...</rant>

XXX: not sure what persistent base does or if it even still works in my branch.