Frees a mid-end structure and all its associated data.
+\H{midend-tilesize}
+
+\c int midend_tilesize(midend *me);
+
+Returns the \cq{tilesize} parameter being used to display the
+current puzzle.
+
+\k{backend-preferred-tilesize}
+
\H{midend-set-params} \cw{midend_set_params()}
\c void midend_set_params(midend *me, game_params *params);