Merge branch 'master' into jgrpp

# Conflicts:
#	src/ai/ai_gui.cpp
#	src/build_vehicle_gui.cpp
#	src/genworld_gui.cpp
#	src/lang/english.txt
#	src/lang/german.txt
#	src/lang/korean.txt
#	src/newgrf_sound.cpp
#	src/roadveh.h
#	src/sound.cpp
#	src/station_cmd.cpp
#	src/train.h
#	src/train_cmd.cpp
#	src/vehicle.cpp
#	src/vehicle_base.h
#	src/vehicle_gui.cpp

src/widgets/vehicle_widget.h

@@ -27,6 +27,7 @@ enum VehicleViewWidgets {
 	WID_VV_SELECT_REFIT_TURN,  ///< Selection widget between 'refit' and 'turn around' buttons.
 	WID_VV_TURN_AROUND,        ///< Turn this vehicle around.
 	WID_VV_FORCE_PROCEED,      ///< Force this vehicle to pass a signal at danger.
+	WID_VV_HONK_HORN,          ///< Honk the vehicles horn (not drawn on UI, only used for hotkey).
 };
 
 /** Widgets of the #RefitWindow class. */