added a log message after pool close

git-svn-id: http://svn.research-infrastructures.eu/public/d4science/gcube/trunk/portal/social-networking-library@130550 82a268e6-3cf1-43bd-a215-b396298e98cf

src/main/java/org/gcube/portal/databook/server/CassandraClusterConnection.java

@@ -87,6 +87,7 @@ public class CassandraClusterConnection {
 			try{
 				_log.info("Closing pool connection");
 				myKeyspace.getConnectionPool().shutdown();
+				_log.info("Pool closed!");
 			}catch(Exception e){
 				_log.error("Unable to close connection pool", e);
 			}