User can touch in to enter station
User can touch out to exit station
User can enter a coach from a station
User can exit coach to station
Train can't have more than 10 coaches
Refactored PassengerHolder
User should be allowed to enter and exit station after touching in and out
User can board coach and alight at station
Coach should be attached to a train
Train can load and unload users at station
Train should only let user enter and exit if stopped
Train should load all users in its coaches