implementato nodeposition con to string e reverse. aggiunto copyright

arraylist/ArrayIndexList.java

@@ -6,6 +6,8 @@ package arraylist;
  * Date: 24/03/14
  * Time: 14:31
  */
+//Copyright (c) 2003 Brown University, Providence, RI
+//Additional modifications and methods by xgiovio
 
     public class ArrayIndexList<E> implements IndexList<E> {
         private E[] array;

arraylist/IndexList.java

@@ -6,6 +6,8 @@ package arraylist;
  * Date: 24/03/14
  * Time: 14:29
  */
+//Copyright (c) 2003 Brown University, Providence, RI
+//Additional modifications and methods by xgiovio
 public interface IndexList<E> {