Payment with a park pass

[koenhendriks]

The current simulator program only implements the payment of normal tickets. We need to implement the payment for parking pass holders. This will involve adding a new class for the parking pass customers which will have its own implementation of the payment. Parking pass holders do not need to go to the payment machines, but can use their cards at the exits.

[JoeyBB91]

1. For this to work, we will need to separate Pass Holders from a normal Customer. This means we will split the type of customers.
2. Every Customer will be registered for their license number, we don't need their names. For Pass Holders however, we can register added specifications. In this case, we DO want their names.

[JoeyBB91]

New plan, we aren't splitting the new Customer class. We are only extending it by giving Pass Holders extra rights. That means that Customer will NOT be an abstract class.