(svn r1323) Adding autoreplace feature

This feature works much like autorenew, but it will get you a new engine type instead of a new one of the same type. Once 
ordered, it will automatically replace the engines while they visits a depot. The GUI for setting this up have been added on the 
vehicle overview windows
Note: autorenew is now autoreplace, but to the same engine type
Nice new features, that was added to make this possible
- windows can now have two independant vertical scrollbars
- CMD_SHOW_NO_ERROR have been added as a flag for DoCommandP. It will make it do the action instead of showing the red box with 
estimated costs even if shift is pressed
- fixed problem where enginetypes where not initialized when loading a game. It's now done in InitializeGame()

vehicle_gui.h

@@ -42,12 +42,13 @@ typedef DEF_SORTER(VehicleSortListingTypeFunctions);
 #define SORT_BY_UNSORTED 0
 extern VehicleSortListingTypeFunctions * const _vehicle_sorter[];
 extern const StringID _vehicle_sort_listing[];
+extern const StringID _rail_types_list[];
 
 enum VehicleSortTypes {
 	VEHTRAIN		= 0,
 	VEHROAD			= 1,
 	VEHSHIP			= 2,
-	VEHAIRCRAFT	= 3
+	VEHAIRCRAFT		= 3
 };
 
 enum {
@@ -56,4 +57,13 @@ enum {
   PLY_WND_PRC__SIZE_OF_ROW_BIG		= 36,
 };
 
+void ShowReplaceVehicleWindow(byte vehicletype);
+
+void Set_DPARAM_Train_Engine_Build_Window(uint16 engine_number);
+void Set_DPARAM_Train_Car_Build_Window(Window *w, uint16 engine_number);
+void Set_DPARAM_Road_Veh_Build_Window(uint16 engine_number);
+void Set_DPARAM_Aircraft_Build_Window(uint16 engine_number);
+void Set_DPARAM_Ship_Build_Window(uint16 engine_number);
+
+
 #endif /* VEHICLE_GUI_H */