Ceph

I guess it's ugly that it echoes it twice. In general, we probably don't need to blast the message out to every possible open log sink on SIGINT, since it's an orderly shutdown.

If we want, we can just ignore SIGINT and SIGTERM in cephtool. Then cephtool will get silently terminated on control-C or killall. The existing signal handler isn't doing any cleanup anyway, just logging.

For programs other than cephtool, I think the existing behavior is fine.