#451 DNS-O-Matic support

[Danesh]

It would good if support for DNS-O-Matic from OpenDNS is added to IpCOP. This will save some resource and bandwidth as IpCOP will only need to update DNS-O-Matic with the updated IP and DNS-O-Matic will update the other dynamic IP services out there.

https://www.dnsomatic.com
https://www.dnsomatic.com/wiki/api