Add a new test for the net ads dns commands ...

[Richard Sharpe]

Hi folks,

Here is a suggested self test for net ads dns register and net ads dns
gethostbyname.

I would have also added a test for net ads dns deregister but it seems
that that code has not been pushed anywhere.

In any event:

1. I am not sure that it should be a samba4 test. Perhaps it should be
a samba3 test.

2. For some reason net ads dns register <name> <IP> -P does not seem
to work in the self-test scripts but it works in a testenv. Clues
appreciated.

-- 
Regards,
Richard Sharpe
(何以解憂？唯有杜康。--曹操)