unbound: add UCI for forward stub and auth zone clauses

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'prefetch_root' options are removed, and superceded by 'zone' section.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>

net/unbound/files/unbound.init

@@ -17,14 +17,14 @@ PROG=/usr/sbin/unbound
 ##############################################################################
 
 boot() {
-  UNBOUND_BOOT=1
+  UB_BOOT=1
   start "$@"
 }
 
 ##############################################################################
 
 start_service() {
-  if [ -n "$UNBOUND_BOOT" ] ; then
+  if [ -n "$UB_BOOT" ] ; then
     # Load procd triggers (rc) and use event IFUP to really start
     return 0
   fi
@@ -35,7 +35,7 @@ start_service() {
 
   # standard procd clause
   procd_open_instance "unbound"
-  procd_set_param command $PROG -d -c $UNBOUND_CONFFILE
+  procd_set_param command $PROG -d -c $UB_TOTAL_CONF
   procd_set_param respawn
   procd_close_instance
 }
@@ -44,7 +44,7 @@ start_service() {
 
 stop_service() {
   # clean up
-  . /usr/lib/unbound/unbound.sh
+  . /usr/lib/unbound/stopping.sh
   unbound_stop
 
   # Wait! on restart Unbound may take time writing closure stats to syslog