cygwin via anonymous cvs

[DJ Delorie]

We now have a public CVS repository from which cygwin developers can
obtain the current development sources.  I've added a web page with
details:

	http://sourceware.cygnus.com/cygwin/cvs.html

I've also modified the nightly snapshots to use this repository
instead of Cygnus's internal repository, as new development will take
place in this new repository from now on.