Chapter 13, Problem 4PP

In this project you will redo Programming Project 8 from Chapter 11 using a linked list instead of an array. As noted there, this is a linked list of double items. This fact may imply changes in some of the member functions. The members are as follows: a default constructor; a member function named addltem to add a double to the list; a test for a full list that is a Boolean-valued function named full(); and a friend function overloading the insertion operator<<.