RFC6303 specifies & recommends following zones not be forwarded
to globally facing servers.
+------------------------------+-----------------------+
| Zone                         | Description           |
+------------------------------+-----------------------+
| 0.IN-ADDR.ARPA               | IPv4 "THIS" NETWORK   |
| 127.IN-ADDR.ARPA             | IPv4 Loopback NETWORK |
| 254.169.IN-ADDR.ARPA         | IPv4 LINK LOCAL       |
| 2.0.192.IN-ADDR.ARPA         | IPv4 TEST-NET-1       |
| 100.51.198.IN-ADDR.ARPA      | IPv4 TEST-NET-2       |
| 113.0.203.IN-ADDR.ARPA       | IPv4 TEST-NET-3       |
| 255.255.255.255.IN-ADDR.ARPA | IPv4 BROADCAST        |
+------------------------------+-----------------------+
Signed-off-by: Kevin Darbyshire-Bryant <kevin@darbyshire-bryant.me.uk>