Use the same seed node list for every node

Otherwise, in this example, if node1 gets restarted, then it will have no way of contacting other nodes that are already in the cluster and it will join itself to form a new cluster.

README.md

@@ -8,15 +8,15 @@ no matter which node receives the message.
 
 run node1:
 
-activator -Dnode.id=1 -Dhttp.port=9000 -Dakka.remote.netty.tcp.port=2551 -Dakka.cluster.seed-nodes.0="akka.tcp://application@127.0.0.1:2551" run
+activator -Dnode.id=1 -Dhttp.port=9000 -Dakka.remote.netty.tcp.port=2551 -Dakka.cluster.seed-nodes.0="akka.tcp://application@127.0.0.1:2551" -Dakka.cluster.seed-nodes.1="akka.tcp://application@127.0.0.1:2552" run
 
 run node2:
 
 activator -Dnode.id=2 -Dhttp.port=9001 -Dakka.remote.netty.tcp.port=2552 -Dakka.cluster.seed-nodes.0="akka.tcp://application@127.0.0.1:2551" -Dakka.cluster.seed-nodes.1="akka.tcp://application@127.0.0.1:2552" run
 
 run node3:
 
-activator -Dnode.id=3 -Dhttp.port=9002 -Dakka.remote.netty.tcp.port=2553 -Dakka.cluster.seed-nodes.0="akka.tcp://application@127.0.0.1:2551" -Dakka.cluster.seed-nodes.1="akka.tcp://application@127.0.0.1:2552" -Dakka.cluster.seed-nodes.2="akka.tcp://application@127.0.0.1:2553" run
+activator -Dnode.id=3 -Dhttp.port=9002 -Dakka.remote.netty.tcp.port=2553 -Dakka.cluster.seed-nodes.0="akka.tcp://application@127.0.0.1:2551" -Dakka.cluster.seed-nodes.1="akka.tcp://application@127.0.0.1:2552" run
 
 For SSL support and configuration in akka please find a valid solution on 
 http://stackoverflow.com/questions/31052582/how-to-configure-akkacluster-using-ssl-support/31163827#31163827