Changes

As we now have wastly vastly different interiors, it is not enough that cabin toy locators for the exterior view are linked to the cabin exclusively. Thus there locators can optionally be locators put into external interior models optionally. If they are not in the external interior model, search falls will fall back to the cabin (or chassis) model to preserve backward compatibility.

Trailers shown in Trailer Browser browser now have separated definitions from Dealer, so it behaves exactly same as truck definitions. Name of folder is ''/def/vehicle/trailer_desktop''.