Remove deprecated information about performances:
* It is better if we leave third parties to do "independent" benchmark.
* We compare Clang (version unspecified) with gcc 4.0 or 4.2.
* The graphs have not been updated for a while.
* Clang is well known now. I don't think we still need to explain why
Clang is great.



git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@207358 91177308-0d34-0410-b5e6-96231b3b80d8
remove useless code

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@207360 91177308-0d34-0410-b5e6-96231b3b80d8
Remove no longer relevant information in the gcc/llvm comparison page + minor updates

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@207361 91177308-0d34-0410-b5e6-96231b3b80d8
remove less relevant information + about packaging/Mac OS X + link to cfe-dev

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@207362 91177308-0d34-0410-b5e6-96231b3b80d8