Configurable clustername

- Configurable clustername for ZooKeeper, Hazelcast, RAMCloud

Change-Id: I2862c7667ece21733f95b25fad3840777314170d
diff --git a/conf/template/hazelcast.xml.template b/conf/template/hazelcast.xml.template
index ce0e53e..0865194 100644
--- a/conf/template/hazelcast.xml.template
+++ b/conf/template/hazelcast.xml.template
@@ -9,6 +9,10 @@
       try to follow the schema defined in the xsd when possible.
   -->
 
+  <group>
+    <name>__HC_CLUSTER__</name>
+  </group>
+
   <properties>
     <property name="hazelcast.logging.type">slf4j</property>
     <property name="hazelcast.version.check.enabled">false</property>