This change standardizes URL examples in tldr-pages
to use the canonical example.com domain.
Pages changed: `dig`, `drill`, `irssi`, `salt`, and `socat`.
Doing a reverse DNS lookup by typing out the IP address in reverse, plus adding .in-addr.arpa to the end is tedious, but fortunately dig has the -x option which makes that process much simpler as one can just feed it a normal IP address.