roles/named: Set minimal responses

Including authority and additional responses in all responses is just a
waste of bandwidth.

roles/named/templates/named.conf.j2

@@ -33,6 +33,7 @@ options {
 {% endif %}
 
 	recursion {{ yesno(named_recursion) }};
+	minimal-responses yes;
 
 	dnssec-enable {{ yesno(named_dnssec) }};
 	dnssec-validation {{ yesno(named_dnssec_validation) }};