travis: Test upgrade to LLVM 3.5 on OS X.
travis: Test upgrade to LLVM 3.5 on OS X.

StanfordLegion/legion,StanfordLegion/legion,StanfordLegion/legion,chuckatkins/legion,sdalton1/legion,chuckatkins/legion,noahdesu/legion,chuckatkins/legion,sdalton1/legion,sdalton1/legion,chuckatkins/legion,chuckatkins/legion,StanfordLegion/legion,sdalton1/legion,noahdesu/legion,StanfordLegion/legion,StanfordLegion/legion,noahdesu/legion,StanfordLegion/legion,sdalton1/legion,noahdesu/legion,noahdesu/legion,sdalton1/legion,chuckatkins/legion,StanfordLegion/legion,chuckatkins/legion