-STACK
-Write line-by-line list of items the player stands on into ./server/out file,
-enclosed by two lines "THINGS_BELOW_PLAYER START" and "THINGS_BELOW_PLAYER END".
+THINGS_HERE [0 to 255] [0 to 255]
+If world exists, write line-by-line list of things at y position of first
+argument, x position of second argument of map into ./server/out file, enclosed
+by two lines "THINGS_HERE START" and "THINGS_HERE END".