OnTouch support when npc is walking (#5134)

* Added support to trigger 'OnTouch'/'OnTouch_' npc label when a npc is moving through npcwalkto script command.
* Fixed #502

Thanks to @aleos89, @wbgneto !

src/map/map.cpp

@@ -2663,7 +2663,7 @@ bool map_addnpc(int16 m,struct npc_data *nd)
 	}
 	// npcs with trigger area are grouped
 	// 0 < npc_num_warp < npc_num_area < npc_num
-	if (xs < 0 && ys < 0)
+	if (xs < 0 || ys < 0)
 		mapdata->npc[ mapdata->npc_num ] = nd;
 	else {
 		switch (nd->subtype) {