Temporary fix for Mavericks: the skin shader isn't getting the color, so just
use white.  We're not using vertex colors on anything skinned yet, anyway.
Merge branch 'master' of https://github.com/worklist/hifi
Merge pull request #1130 from ey6es/master

Temporary fix for Mavericks: ignore the per-vertex color on skinned meshes (they don't yet need them).