Automatically replace IP with rDNS

[Artoria2e5]

I've done a bit of a hacky job to automatically replace IP with rDNS'ed name in Artoria2e5@a5cec25. If anyone wants it, you are welcome to take it!

It looks like if you don't make a titles it will default to creating a graph for everything due to

chrony-graph/bin/offset-graph

Line 21 in b26fd34

echo $stat ${stat#statistics.}

. This seems to be intended and not due to my change, but I am just a bit too full from lunch to want to brave a PR right now.