@Override
    public AddEdgeStartStep clone() {
        final AddEdgeStartStep clone = (AddEdgeStartStep) super.clone();
        clone.parameters = this.parameters.clone();
        return clone;
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/AddEdgeStartStep.java