(svn r3058) The default AI may not build dual headed trains under certain circumstances.
Simplify this check by testing the rail vehicle info flags instead of passing a global variable around.
Note: This is not exactly the original behaviour, because the Lev4 was always allowed to be built, but i guess that was a glitch.

/* $Id$ */

// stdafx.cpp : source file that includes just the standard includes
//	ttd.pch will be the pre-compiled header
//	stdafx.obj will contain the pre-compiled type information

#include "stdafx.h"

// TODO: reference any additional headers you need in STDAFX.H
// and not in this file