added system tests

bin/tests/system/dnssec/ns2/example.db.in

@@ -0,0 +1,24 @@
+$TTL 300	; 5 minutes
+@			IN SOA	mname1. . (
+				2000042407 ; serial
+				20         ; refresh (20 seconds)
+				20         ; retry (20 seconds)
+				1814400    ; expire (3 weeks)
+				3600       ; minimum (1 hour)
+				)
+			NS	ns2
+ns2			A	10.53.0.2
+
+a			A	10.0.0.1
+b			A	10.0.0.2
+d			A	10.0.0.4
+
+; A secure subdomain
+secure			NS	ns.secure
+ns.secure		A	10.53.0.3
+
+; An insecure subdomain
+insecure		NS	ns.secure
+ns.insecure		A	10.53.0.3
+
+z			A	10.0.0.26