Added a preference factory and updated existing specs to use it.
Added factories to the reservation and flight factory so that if they aren't provided with ID's for their components, they create their own objects and use those object's ids.
Wrote a reservation factory and updated all existing specs to use it.
Added a flight_reservation factory and updated all specs to use it.
Built a frequent_flier_client factory and updated all existing specs to use it.
Added a plane factory and updated all existing specs to use it. flight_controller#filter does not yet have proper factories.