gc1_user_stories.js

var SUM pseudocode: add up all the numbers in an array


var MEAN pseudocode: divide the sum of an array by the length of that array.

Var MEDIAN pseudocode: use array.sort to order the numbers in our array from smallest to lartest
then (if array length is odd): find the midpoint of that array 
or (if array length is even): find the two numbers that sit on either side of array.length/2