internal void AddTimer(float duration, Action callback)
        {
            CallbackTimer callbackTimer = new CallbackTimer(duration, new List <Action>()
            {
                callback
            });

            timers.Add(callbackTimer);
        }
        internal void AddTimer(float duration, List <Action> callbacks)
        {
#if UNITY_EDITOR
            if (callbacks == null)
            {
                Debug.LogWarning("CallbackTimerManager.cs :: Callback list was null");
                return;
            }
#endif

            CallbackTimer callbackTimer = new CallbackTimer(duration, callbacks);

            timers.Add(callbackTimer);
        }