code: public CassandraJavaRDD<R> toEmptyCassandraRDD() {
          CassandraRDD<R> newRDD = rdd().toEmptyCassandraRDD();
          return wrap(newRDD);
      }
docs: Produces the empty CassandraRDD which has the same signature and properties, but it does not
  perform any validation and it does not even try to return any rows.