[rancid] rancid extension to pass commit message

[heasley]

Wed, Dec 21, 2016 at 05:50:11PM +0000, Mischa Diehm:
> Hi,
> 
> First of all thanks for this great and useful software. We use it
> extensively and are very happy with it!
> 
> History for the diff: Since some time we use elasticsearch and logstash for
> our central NOC log management system. To detect changes on our devices
> (firewalls, routers, switches Š) we check for specific log lines and trigger
> a rancid-run from there. Usually we see in the logline who has made the
> change. To have this visible in our commit message and our mails received
> from rancid I have extended rancid-run and control_rancid to be able to pass
> a commit message like:
> 
> # rancid-run  -c "$msg³
> (diff attached)
> 
> What do you think is this sth. useful and worth adding?

Yes, the idea seems fine to me.  I'll add it for rancid 4.0.