on Ubuntu 14.04.1 LTS if nsupdate runs without port number given it treated argument following server name as port number.
and throws error:
```
port 'update' is not numeric
syntax error
```
The gandi api has changed its url for a more stable
one. Although https://dns.beta.gandi.net will continue to
work for the foreseable future, this commits updates the
url to new official one.