implementato nodeposition con to string e reverse. aggiunto copyright

deque/NodeDeque.java

@@ -9,6 +9,8 @@ import exceptions.EmptyDequeException;
  * Date: 17/03/14
  * Time: 16:26
  */
+//Copyright (c) 2003 Brown University, Providence, RI
+//Additional modifications and methods by xgiovio
 public class NodeDeque<E> implements Deque <E>  {
 
     public NodeDeque(){