New commands to add and remove DNS entries

- Commands dns-add and dns-remove added to weave script
- Updated documentation for WeaveDNS
- Added test script for dns-add and dns-remove
- Added IP address functions matching existing CIDR ones

test/240_dns_add_name_test.sh

@@ -0,0 +1,29 @@
+#! /bin/bash
+
+. ./config.sh
+
+C1=10.2.0.78
+C2=10.2.0.34
+NAME1=seeone.weave.local
+NAME2=seetwo.weave.local
+
+start_suite "Add and remove names on a single host"
+
+weave_on $HOST1 launch-dns 10.2.254.1/24
+
+weave_on $HOST1 run $C2/24 -t --name=c2 ubuntu
+weave_on $HOST1 run --with-dns $C1/24 -t --name=c1 aanand/docker-dnsutils /bin/sh
+
+weave_on $HOST1 dns-add $C2 c2 -h $NAME2
+
+assert_dns_record $HOST1 c1 $NAME2 $C2
+
+weave_on $HOST1 dns-add $C1 c1 -h $NAME1
+
+assert "exec_on $HOST1 c1 getent hosts $C1 | tr -s ' '" "$C1 $NAME1"
+
+weave_on $HOST1 dns-remove $C1 c1
+
+assert_raises "exec_on $HOST1 c1 getent hosts $NAME1" 2
+
+end_suite