Tracks customers & their orders of pizzas and drinks.
/ - displays welcome message
/allCustomers - gets all customer info
/customer/:id - gets that customer's details
/customer/:id/orders - gets all orders placed by that customers, including drinks and pizzas
/drinks - gets all drinks
/drinks/:id - gets details of that drink
/drinks/suppliers/:supplierName - gets all drinks sold by that supplier
/pizzas - gets all pizzas
/pizzas/:id - gets that pizza's details
/pizzas/:id/toppings - gets that pizza's toppings