docs/176435: [patch] [articles/committers-guide] update gnats mirroring section

[eadler at FreeBSD.org]

Synopsis: [patch] [articles/committers-guide] update gnats mirroring section

Responsible-Changed-From-To: freebsd-doc->eadler
Responsible-Changed-By: eadler
Responsible-Changed-When: Wed Feb 27 22:13:17 UTC 2013
Responsible-Changed-Why: 
I'll take it.

http://www.freebsd.org/cgi/query-pr.cgi?pr=176435