Support ANSI escape code on Windows

In some cases (e.g. when a build system pipes stderr) the Windows console
API cannot be used to color output. For these, provide a way to switch to
ANSI escape codes. This is required for Clang's -fansi-escape-codes option.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190460 91177308-0d34-0410-b5e6-96231b3b80d8
Get rid of unused isPodLike definitions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190461 91177308-0d34-0410-b5e6-96231b3b80d8