Finished part 2 of assignment 4.

Calculates the Euclidean Distance of 2 lists of numbers. Raises an exception if
the lists are of inequal lengths. Otherwise, calculates the distance.
Unit Test for Euclidean Distance Function

Time to give TDD a go.
Calculates Euclidean Distance, Problem 4.2
Bad commit...Too many things done.

Changed the name of euclidean_distance to assignment_4 to hold all the files. Added series function and unittest for it.
Completed unit test for Part 4
Fixed Test Case for part 4.
Added part 4