Using the application developed thus far, create a list management application.  Include buttons to add items to the list, or to delete the selected item from the list.  If no item is selected for deletion, then an error message must be displayed.  The count for the number of items included in the list must be displayed below the list, with an appropriate message: “There are currently … items in the list.”  You are welcome to enhance your application with comments, messages and graphics.  Duplicates may not be entered onto the list.  An appropriate error message must be displayed.