Fix SLIVR, introduce Raycasting: SLIVR, more coherent renderer dialog, add support for trilinear interpolation in raycasters.

git-svn-id: svn+ssh://portal-auth.nersc.gov/project/projectdirs/visit/svn/visit/branches/2.7RC/src@21926 18c085ea-50e0-402c-830e-de6fd14e8384
remove udaReaderMTMD from databases CMakeLists.txt

git-svn-id: svn+ssh://portal-auth.nersc.gov/project/projectdirs/visit/svn/visit/branches/2.7RC/src@21929 18c085ea-50e0-402c-830e-de6fd14e8384