Merge branch 'custom_bridgeheads' into jgrpp

# Conflicts:
#	docs/landscape.html
#	src/bridge_map.h
#	src/pbs.cpp
#	src/saveload/company_sl.cpp
#	src/saveload/extended_ver_sl.cpp
#	src/settings_type.h
#	src/signal.cpp
#	src/train_cmd.cpp
#	src/tunnel_map.h
#	src/tunnelbridge_cmd.cpp
#	src/tunnelbridge_map.h
#	src/vehicle.cpp
#	src/viewport.cpp

src/vehicle_func.h

@@ -61,7 +61,7 @@ void ViewportAddVehicles(DrawPixelInfo *dpi);
 void ViewportMapDrawVehicles(DrawPixelInfo *dpi);
 
 void ShowNewGrfVehicleError(EngineID engine, StringID part1, StringID part2, GRFBugs bug_type, bool critical);
-CommandCost TunnelBridgeIsFree(TileIndex tile, TileIndex endtile, const Vehicle *ignore = NULL);
+CommandCost TunnelBridgeIsFree(TileIndex tile, TileIndex endtile, const Vehicle *ignore = NULL, bool across_only = false);
 
 void DecreaseVehicleValue(Vehicle *v);
 void CheckVehicleBreakdown(Vehicle *v);