stale link on "Port description for misc/xpns"

[Doug Barton]

Ralf Valerien wrote:
> Hi,
> 
> on your page "Port description for misc/xpns"
>   http://www.FreeBSD.org/cgi/url.cgi?ports/misc/xpns/pkg-descr
> 
> the link
>   http://www.ee.uwa.edu.au/~braunl/pns/
> is broken. It should read
>   http://robotics.ee.uwa.edu.au/pns

Done.