1) I modified the build of cmake in build_visit to apply the cmake 2.8.10.2
   patch to cmake 2.8.12.2 as well. This resolves #2041.

2) I noticed that build_visit hung downloading mesa 7.10.2 and discovered
   that the URL for it was no longer valid. I removed the URL so that it 
   would grab it from the repository at NERSC.



git-svn-id: http://visit.ilight.com/svn/visit/trunk/src@24924 18c085ea-50e0-402c-830e-de6fd14e8384