Merge branch 'as/doc-for-devs'

It might be a better idea to move the text the bottom one adds to
the extended description from the quick checklist part.

* as/doc-for-devs:
  Documentation: move support for old compilers to CodingGuidelines
  SubmittingPatches: add convention of prefixing commit messages

diff --cc Documentation/SubmittingPatches
Simple merge