A couple plots were manually initializing GLEW.  This makes them
use the new avtGLEWInitializer, meaning 1) if both plots are used
in a session, GLEW shouldn't get initialized twice, and 2) they
can work against Mesa, and thus in SR mode.

git-svn-id: http://visit.ilight.com/svn/visit/trunk/src@8022 18c085ea-50e0-402c-830e-de6fd14e8384