[PATCH] Add commit message guidelines to developer policy

[Renato Golin]

In http://reviews.llvm.org/D8197#140231, @sanjoy wrote:

> I tend to add a prefix like `[IRCE]` or `[SCEV]` to the subject of my commit messages to quickly establish context.  I've seen others do it too.  Does it make sense to codify that practice as a suggestion in this document?


This is a good point, I'll add a comment to that effect.


REPOSITORY
  rL LLVM

http://reviews.llvm.org/D8197

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