(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.

/* $Id$ */

#ifndef DRIVER_H
#define DRIVER_H

void LoadDriver(int driver, const char *name);

bool GetDriverParamBool(const char* const* parm, const char* name);
int GetDriverParamInt(const char* const* parm, const char* name, int def);

void GetDriverList(char* p);

#endif /* DRIVER_H */