Merge branch 'reverse_at_waypoint' into jgrpp

Conflicts:
	src/order_gui.cpp
	src/saveload/extended_ver_sl.cpp
	src/saveload/extended_ver_sl.h
	src/train_cmd.cpp

src/train.h

@@ -113,6 +113,8 @@ struct Train FINAL : public GroundVehicle<Train, VEH_TRAIN> {
 	/** Ticks waiting in front of a signal, ticks being stuck or a counter for forced proceeding through signals. */
 	uint16 wait_counter;
 
+	uint16 reverse_distance;
+
 	/** We don't want GCC to zero our struct! It already is zeroed and has an index! */
 	Train() : GroundVehicleBase() {}
 	/** We want to 'destruct' the right class. */