add coords tutorial for ds shapes

pd/doc/4.data.structures/pd-l2ork/ds-tutorials/17.coords.pd

+#N struct drawtut-coords float x float y;
+#N canvas 1 25 537 571 10;
+#N canvas 290 275 450 300 META 0;
+#X text 16 6 KEYWORDS tutorial data_structure draw;
+#X text 16 26 LICENSE SIBSD;
+#X text 16 66 AUTHOR Jonathan Wilkes;
+#X text 16 86 HELP_PATCH_AUTHORS Jonathan Wilkes;
+#X text 16 46 DESCRIPTION animating scalars with the [draw] command
+;
+#X restore 450 538 pd META;
+#X text 0 1 New Drawing Commands: coordinate data;
+#X text 1 1 _____________________________________;
+#X obj 51 30 struct drawtut-coords float x float y;
+#X obj 135 321 draw polyline;
+#X scalar drawtut-coords 85 159 \;;
+#X obj 135 113 tgl 15 0 empty empty Auto 17 7 0 10 -262144 -1 -1 0
+1;
+#X obj 135 133 metro 400;
+#X obj 135 155 tgl 15 0 empty empty Click_me 17 7 0 10 -262144 -1 -1
+0 1;
+#X obj 135 182 * 30;
+#X obj 135 204 + 30;
+#X msg 135 231 points 0 0 30 0 30 \$1 0 \$1;
+#X obj 158 256 loadbang;
+#X msg 158 278 stroke black \, stroke-width 1 \, fill none \, points
+0 0 30 0 30 30 0 30;
+#X obj 46 431 draw path m -60 20 20 0 0 20 -20 0 z m 30 0 10 0 0 10
+-10 0 z;
+#X msg 46 406 d m -60 20 20 0 0 20 -20 0 z m \$1 0 10 0 0 10 -10 0
+z;
+#X text 184 189 Polygons and polylines take the "points" message to
+set their coordinate data.;
+#X text 94 371 For paths \, use the "d" message to send new path data.
+;
+#X text 49 64 You can dynamically set the coordinate data for polygons
+\, polylines \, and paths.;
+#X connect 6 0 7 0;
+#X connect 7 0 8 0;
+#X connect 8 0 9 0;
+#X connect 9 0 10 0;
+#X connect 10 0 11 0;
+#X connect 10 0 15 0;
+#X connect 11 0 4 0;
+#X connect 12 0 13 0;
+#X connect 13 0 4 0;
+#X connect 15 0 14 0;