public static void AddWithExitEvent <TState, TTrigger>(this IStateMachine <TState, TTrigger> fsm, TState stateId, Action onExit)
 {
     fsm.AddWithEvents(stateId, null, null, onExit);
 }
 public static void AddWithUpdateEvent <TState, TTrigger>(this IStateMachine <TState, TTrigger> fsm, TState stateId, Action onUpdate)
 {
     fsm.AddWithEvents(stateId, null, onUpdate, null);
 }
 public static void AddWithEnterEvent <TState, TTrigger>(this IStateMachine <TState, TTrigger> fsm, TState stateId, Action onEnter)
 {
     fsm.AddWithEvents(stateId, onEnter, null, null);
 }