/// <summary>
 /// Get the first instance of a manager matching the given type.
 /// </summary>
 /// <typeparam name="T"></typeparam>
 /// <returns> The manager, if found, or the default of the given type. </returns>
 public static T GetFirstManager <T>() where T : IManager
 {
     if (instance != null) // Ensure the instance exists
     {
         return(instance.GetFirst <T>());
     }
     else // Instance doesn't exist, cannot get manager
     {
         return(default(T));
     }
 }