Update room

Rewrote the code to facilitate the change that the Door objects now contain Room objects rather than just strings. Also added a basic hasAccess method to have the Room test whether a Person is allowed in. Added a personEnter method that allows the system to ask whether a person is allowed to enter the current room and carry out appropriate changes.
Note the updatePeople should only be used by Room objects. There is no reason for Doors or Persons to have access to that method.