nightly builds moved to hudson

Nutch's nightly builds have been moved to a Hudson server
at:

   http://lucene.zones.apache.org:8080/hudson/job/Nutc
h-Nightly/

I've stopped the old nightly build process and added a
redirect from the 
old nightly build distribution directory to this page.

Thanks to Nigel Daley for configuring and maintaining the
Hudson server!

Doug