* no need to export libcling's (and thus clang's) symbols that are used in TCintWithCling.
* properly hides clang, llvm symbols (they are now unreachable through ROOT)
* rootcling_tmp doesn't need to find libCling.so anymore

The order of static initialization is (as always) fragile but relevant, as TCintWithCling is created during static init, but it needs parts of llvm to be set up before. Re-ordering of $(CLINGLIBEXTRA) versus $(COREO) fixes that for me.


git-svn-id: http://root.cern.ch/svn/root/trunk@45778 27541ba8-7e3a-0410-8455-c3a389f83636