(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()

lang/english.txt

@@ -2763,3 +2763,25 @@ STR_SCHEDULED_TRAINS_TIP					:{BLACK}Show all trains which have this station on
 STR_SCHEDULED_ROAD_VEHICLES_TIP					:{BLACK}Show all road vehicles which have this station on their schedule
 STR_SCHEDULED_AIRCRAFT_TIP					:{BLACK}Show all aircraft which have this station on their schedule
 STR_SCHEDULED_SHIPS_TIP						:{BLACK}Show all ships which have this station on their schedule
+
+STR_REPLACE_VEHICLES						:{BLACK}Replace Vehicles
+STR_REPLACE_VEHICLES_START					:{BLACK}Start Replacing Vehicles
+STR_REPLACE_VEHICLES_STOP					:{BLACK}Stop Replaing Vehicles
+STR_NOT_REPLACING						:{BLACK}Not replacing
+STR_NOT_REPLACING_VEHICLE_SELECTED				:{BLACK}No vehicle selected
+STR_REPLACE_HELP_LEFT_ARRAY					:{BLACK}Select a type of engine to replace{}Select an engine on the right side to replace to
+STR_REPLACE_HELP_RIGHT_ARRAY					:{BLACK}Select an engine to replace to{}It will replace the engines selected on the left side
+STR_REPLACE_HELP_STOP_BUTTON					:{BLACK}Press this button if you don't want to replace the engine, you selected on the left
+STR_REPLACE_HELP_START_BUTTON					:{BLACK}Press this button if you want to replace the engine selected on the left with the one selected on the right
+STR_REPLACE_HELP_RAILTYPE					:{BLACK}Select a railtype you want to select engines for
+STR_REPLACE_HELP_REPLACE_INFO_TAB				:{BLACK}This displays what engine the selected engine on the left are being replaced to
+STR_REPLACE_HELP						:{BLACK}This feature allows you to select an enginetype and replace that one with another one. This will then be done automatically when the vehicles enters a depot anyway
+
+############ Lists rail types
+
+STR_RAIL_VEHICLES						:{BLACK}Rail Vehicles
+STR_MONORAIL_VEHICLES						:{BLACK}Monorail Vehicles
+STR_MAGLEV_VEHICLES						:{BLACK}Maglev Vehicles
+
+############ End of list of rail types
+