title: Unity EventManager with delegate instead of UnityEvent
body: <p>I am looking for c# delegate version of this <a href="https://unity3d.com/learn/tutorials/topics/scripting/events-creating-simple-messaging-system" rel="nofollow noreferrer">Manager using UnityEvent</a>. I don't want to use this because <a href="https://docs.unity3d.com/ScriptReference/Events.UnityEvent.html" rel="nofollow noreferrer">UnityEvent</a> is slower than C# event at most time.</p>
  
  <p>Any clue on how to implement this? </p>