Fix named.conf man page documentation

Commit 4ca74eee49 update the zone grammar
such that the zone statement is printed with the valid options per
zone type.

This commit is a follow-up, putting back the ZONE heading and adding
a note that these zone statements may also be put inside the view
statement.

It is tricky to actually print the zone statements inside
the view statement, and so we decided that we would add a note to say
that this is possible.

bin/named/named.conf.rst

@@ -885,6 +885,11 @@ VIEW
   	zone-statistics ( full | terse | none | boolean );
   };
 
+ZONE
+^^^^
+
+Any of these zone statements can also be set inside the view statement.
+
 .. include:: ../../doc/misc/primary.zoneopt.rst
 .. include:: ../../doc/misc/secondary.zoneopt.rst
 .. include:: ../../doc/misc/mirror.zoneopt.rst

doc/man/named.conf.5in

@@ -974,6 +974,9 @@ view string [ class ] {
 .fi
 .UNINDENT
 .UNINDENT
+.SS ZONE
+.sp
+Any of these zone statements can also be set inside the view statement.
 .INDENT 0.0
 .INDENT 3.5
 .sp

doc/misc/rst-options.pl

@@ -79,6 +79,8 @@ while (<FH>) {
 	}
 }
 
+my $UNDERLINE;
+
 my $blank = 0;
 while (<FH>) {
 	if (m{// not.*implemented} || m{// obsolete} ||
@@ -97,7 +99,7 @@ while (<FH>) {
 	s{        }{\t}g;
 	if (m{^([a-z0-9-]+) }) {
 		my $HEADING = uc $1;
-		my $UNDERLINE = $HEADING;
+		$UNDERLINE = $HEADING;
 		$UNDERLINE =~ s/./^/g;
 		print $HEADING . "\n";
 		print $UNDERLINE . "\n\n";
@@ -123,6 +125,12 @@ while (<FH>) {
 
 }
 
+print "ZONE\n";
+$UNDERLINE = "ZONE";
+$UNDERLINE =~ s/./^/g;
+print $UNDERLINE . "\n\n";
+print "Any of these zone statements can also be set inside the view statement.\n\n";
+
 print <<END;
 .. include:: ../../doc/misc/primary.zoneopt.rst
 .. include:: ../../doc/misc/secondary.zoneopt.rst