use CloudFlare, Quad9 and Google as example forwarders

bind/bind.spec

@@ -36,7 +36,7 @@ Class:        BASE
 Group:        DNS
 License:      ISC
 Version:      %{V_opkg}
-Release:      20180314
+Release:      20180401
 
 #   package options
 %option       with_dnssec    yes

bind/bind.txt

@@ -60,6 +60,7 @@ options {
     #query-source        address 127.0.0.1 port *;
     #transfer-source     127.0.0.1;
     #notify-source       127.0.0.1;
+    #forwarders          { 1.1.1.1; 9.9.9.9; 8.8.8.8; };
 };
 
 zone "." IN {