+ Refactored Artikel into Article
+ Refactored Dienblad into Tray
+ Refactored Persoon into Person
+ Refactored KassaLijn into CheckoutLine
+ Tray and KassaRij updates
+ Implemened CashRegister class
+ Added Canteen class
+ Implemented Canteen constructor
+ Bit of refectoring. eerstePersoonInRij -> getFirstPersonInLine
+ Implemented method to add a new person in line (Canteen)
+ Implemented a method to process people in line for checkout
+ Made class variables private
+ Implemented method to fetch amount of money in the cash register
+ Implemented method to get the amount of articles that passed the cash register in a canteen
+ Implemented method to reset the canteen's cash register
+ Added task 5a into the readme
+ Added CanteenSimulation class
+ Implemented CanteenSimulation constructor
+ Implemented canteen simulation
+ Documentation for the Canteen class