Wired-up the new LLVM diagnostic system into clang diagnostic system.
The approach is similar to the existing inline-asm reporting, just more
general.

<rdar://problem/15886278>


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@200931 91177308-0d34-0410-b5e6-96231b3b80d8