On small networks there are not a lot of OLSR name changes. While
dnsmasq watches for changes and updates itself, it will sometimes miss
them. On busy networks this doesnt matter as the next change will catch
it up. But on smaller network (esp. test networks) a missed change can
stop name resolution working for some time. So now, if no changes are
detected for > 60 seconds, we force dnsmasq to reload its tables.
* Dont display previous neighbors with empty hostnames
* Use IP address when name missing
* Fix bug where missing names became ever growing string of whitespace
Tim Wilkinson