[PATCH] Allow Clang tools to display an overview when using the CommonOptionsParser.

[Guillaume Papin]

  Oh, I see, thanks for letting me know. I will keep this in mind in the future.
  Can you (or someone else) commit it for me?

  Thanks.

http://llvm-reviews.chandlerc.com/D1185

BRANCH
  tool-cli-overview

ARCANIST PROJECT
  clang