With growing interest, DNS over TLS can be setup in Unbounds foward-zone:
clause. A broader UCI solution is added to support forward-, stub-, and
auth- zone clauses in a new 'zone' section. This implentation required
reworking scripts, because they did not scale. 'forward_domain' and
'prefetch_root' options are removed, and superceded by 'zone' section.

Signed-off-by: Eric Luehrsen <ericluehrsen@gmail.com>

- Add domain_forward to permit designated domains to forward instead
  of recurse as listed in resolve.conf.auto from DHCP WAN client
- Update rebind_protection and add rebind_interface to protect IP6
  GLA locally just like RFC 1918 protection
- Rename trigger to trigger_interface with backwards compatability
- Update odhcpd script for efficiency handling many clients

Signed-off-by: Eric Luehrsen <ericluehrsen@hotmail.com>

Unbound UCI tries to protect embedded flash from excess
use. Unbound RFC5011 KSK tracking can rewrite root.key
every few minutes to an hour. It also writes and destroys
files in the same directory during the process.

Recommended UCI delays for copying busy work in /var/
back to /etc/ may be too conservative. These are all
changed from 28 to 9 days.

The RFC5011 KSK results were also destroyed by an
init.d restart, even if /var/ is mounted on persistent
storage like USB drive. /var/lib/unbound/root.key is
now preserved during this process, unless a newer key
is installed in /etc/ manually or package update.

Signed-off-by: Eric Luehrsen <ericluehrsen@hotmail.com>

-unbound.sh implements the majority of requirements in README.md
-rootzone.sh reloads a small subset for alternate trigger maintenance
-unbound.init sets procd triggers on Unbound and dnsmasq (dhcp) UCI
-two part commit squashed with Makefile included

Signed-off-by: Eric Luehrsen <ericluehrsen@hotmail.com>

-Unbound RFC 5011 is busy and writes frequently
-RFC 5011 creates working files in same directory
-DNSSEC root.key managed in /var/lib/unbound
-Protect against flash ROM wear out in /etc/unbound
-Scripts will copy back every 7 days instead

Signed-off-by: Eric Luehrsen <ericluehrsen@hotmail.com>