Alert on new public IP address with GeoIP and latency

[pirate]

I'm splitting this out from #24. I want to add an alert whenever your public IP changes.

I can easily get GeoIP from the public IP, and display latency by pinging 8.8.8.8. This will create a useful alert that shows the following:

local IP <latency ms> public ip (geolocation)

The command to get the new public ip is:
dig +short myip.opendns.com @resolver1.opendns.com -> 123.123.123.123

The command to get the GeoIP reported city is (requires brew install geoip):
geoiplookup 123.123.123.123 | tail -1 | perl -pe 's/.*?: .*?, .., .*?, //g' | perl -pe 's/, .*$//g' -> Montréal

The command to get the latency is:
ping -c 1 -t 1 8.8.8.8 | tail -1 | perl -pe 's/^(.* = \d*\.\d*\/)(\d*)(.\d*\/.*)$/$2 ms/gm' -> 19ms