it would be conceivable to integrate this with the bot driving this
script, so the message would be appended only to the first patchset in a
change, or even only to the first complaint (within a while) for any
particular contributor.

Change-Id: I5a7e3265dea8a3e24649d223fdd6e96c886eebc1
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>