Original title: Include resolved IP address in rs.status() and rs.conf()

We often have to troubleshoot replication issues. It would be handy to include the IP address the DNS entry resolves to (from the MongoDB perspective) to help with diagnostics.

For example

2016-07-25T09:02:19.834-0400 I NETWORK  [ReplExecNetThread-49255] Socket closed remotely, no longer connected (idle 6 secs, remote host 10.71.219.130:27017)
2016-07-25T09:02:19.879-0400 W NETWORK  [ReplExecNetThread-49255] Failed to connect to 10.71.219.130:27017, reason: errno:111 Connection refused

I'd like to more easily associate these with a node. Alternatively, perhaps include the host in the logging? Or both?