Tag build swift-DEVELOPMENT-SNAPSHOT-2016-10-06-a
Merge remote-tracking branch 'origin/swift-3.1-branch' into stable

* origin/swift-3.1-branch:
  [sanitizer] Fixup 2: Do not introduce __sanitizer namespace globally
  [sanitizer] Fixup: Do not introduce __sanitizer namespace globally
  [compiler-rt] Remove the system includes from __sanitizer namespace
  [compiler-rt] Do not introduce __sanitizer namespace globally