. The following program only tests the tail method in the List object, your job is to test all the other methods (15 pts)
https://github.com/PacktPublishing/Learning-Functional-Data-Structures-and-Algorithms/blob/master/Chapter03/List.scala
Note that the current List object extends App, which is usually not the case when we design a class.
2. Read the List.scala file posted on Moodle and write a test program (which has a main method) to test some of its methods. (5 pts)
3. Modify the List object in 1. by following the design of the List class in 2. (so it does not extends App) and then test all its methods again as you did in 2. (30 pts)
