bug#22396: support for single-request

[Ian Jackson]

Eugene Yunak writes ("bug#22396: support for single-request"):
> Package: adns
> 
> It appears adns does not recognize and support the `single-request`
> option from resolv.conf, here's the relevant error message:
> 
> adns: /etc/resolv.conf:2: unknown option `single-request'

Indeed it doesn't.  I'm afraid I don't have time right now to
implement this.  I have some bugfixes that I ought to have released
some time ago...

In the meantime I suggest using a local caching resolver.  This is
better for caching etc. anyway.

Ian.