Added DNS dynamic update support by just inventing a key
and doing all the setup work for that.  I think there is still
one problem... it doesn't set the mode bits on the files created in
/var/bind/...
dns dyn update consists of:
        create random id for dns updates
	add --probe option, which calls dnssec-keygen to create a key.
	extract the key info to put it in to named.conf.files...
        and ndwatch.conf