Added initialize method to BigRig which defaults the number of wheels to 18, and sets color using super. Also added honk method to BigRig
Added Motorcycle class, which is a subclas of Car. It defaults its values to color of red and wheels of 2.
Added initialize method to CarStats which holds a color. Also added 2 class methods, one to calculate the top choice of car color and one to calculate the least choice of car color.