/// <summary>
 /// Removes a receiver from the list.
 /// </summary>
 /// <returns>true if the item was in the list, false otherwise</returns>
 public bool RemoveReceiver(IRigidBodyEventReceiver receiver)
 {
     return(receivers.Remove(receiver));
 }
 /// <summary>
 /// Adds a receiver to the list. Does not check for duplicates.
 /// </summary>
 public void AddReceiver(IRigidBodyEventReceiver receiver)
 {
     receivers.Add(receiver);
 }