code: public Vertigo getCluster(String address, Handler<AsyncResult<Cluster>> resultHandler) {
      Cluster cluster = new DefaultCluster(address, vertx, container);
      cluster.ping(resultHandler);
      return this;
    }
docs: Loads a cluster.
  
  @param address The cluster address.
  @param resultHandler An asynchronous handler to be called once complete.
  @return The Vertigo instance.