Fixed an invalid reference to the Event class.
Fixed an invalid @return tag.
Renamed the FSM::getID() method to getFSMID().
Renamed the IState::getID() method to getStateID().
Added missing type hintings.
Added missing PHPDoc to the State::getEvent() method.
Renamed the Event::getID() method to getEventID().
Renamed the interface IState to StateInterface.
Renamed the FSM::$id field to $fsmID.
Renamed the local variable $id to $fsmID in the FSM::__construct() method.
Renamed the State::$id field to $stateID.
Renamed the Event::$id field to $eventID.
Renamed the local variable $id to $eventID in the Event::__construct() method.
Renamed the local variable $id to $stateID in the State::__construct() method.
Renamed the local variable $id to $eventID in the State::getEvent() method.
Renamed the local variable $id to $eventID in the State::hasEvent() method.
Removed the FSM::hasEvent() method.