Explosive cart in multiplayer works but is invisible #41

• give ExplosiveCartItem
• Place the cart on some rails, ideally going downhill so it'll move
• Have an activator rail on the track somewhere - give ActivatorRail
• Observe that the cart never becomes visible, but server logging indicates it is created. It'll roll down the hill, trigger off the activator, and explode a few seconds later

Probably something isn't marked right for the cart to become visible on clients

Edit: Seems to be the case with several newer carts (all from AdditionalRails?)