Attach bind-9.2.4rc4 to the base system. Rip out bind-8 binaries and add

Attach bind-9.2.4rc4 to the base system.  Rip out bind-8 binaries and add
in / adjust for most bind-9 binaries.  Note that some pre-generated header
files have been hacked into /usr/src/usr.sbin/named and might have to be
regenerated from the original distribution when incorporating updates to
bind.  But, for the most part, the build is clean.

Clean up rc.d/named and etc/defaults/rc.conf, add a README file to
/etc/namedb describing setup requirements, and change the default
named.conf file and RCNG variables to (if named is enabled) run named in
a chrooted environment as user 'bind'.  Adapt the 'getroot' script that
I have used for many years to provide a better root.zone master methodology
instead of the root hints file that has been traditionally shipped.

Adjust the mtree files and distrib-dirs target to create the necessary
infrastructure in /etc/namedb for handling a chrooted named.

NOTE: bind-8 had 'ndc' and 'named-xfer'.  bind-8 has rndc and there is no
named-xfer (it is builtin to named).  nslookup still exists but is deprecated
in favor of 'dig', and the old dnskeygen/dnsquery mechanism has been replaced
by the newer dnssec-* mechanism.