Add TODO

Author: garydgregory

src/main/java/org/apache/commons/io/input/BoundedInputStream.java

@@ -36,6 +36,8 @@
  * @since 2.0
  */
 public class BoundedInputStream extends FilterInputStream {
+    
+    // TODO For 3.0, extend CountintInputStream.
 
     /**
      * Builds a new {@link BoundedInputStream} instance.