Doc tweaks.
Doc tweaks.

Suggested by: Grzegorz Adam Hankiewicz <gradha@titanium.sabren.com>

* HACKING
  (Patch submission guidelines): Revise attachment policy, to match
    current consensus and www/mailing-list-guidelines.html.
  (Writing log messages): Clarify need for consistency.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion