Add llvm::for_each as a range-based extensions to <algorithm> and make use of it in some cases where it is a more clear alternative to std::for_each.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317356 91177308-0d34-0410-b5e6-96231b3b80d8
12 files changed