Update SUMMARY with current reference APIs. (#507)

docs/reference/game/delete.md

@@ -0,0 +1,26 @@
+# delete
+
+Delete a sprite from the game.
+
+```sig
+let item: game.LedSprite = null;
+item.delete();
+```
+
+### Parameters
+
+* the **sprite** you want to delete from the game
+
+### Example
+
+This program makes a sprite and shows the number of its brightness on the screen. Then, it deletes the sprite. 
+
+```blocks
+let ball = game.createSprite(0, 2);
+basic.showNumber(ball.get(LedSpriteProperty.Brightness));
+ball.delete();
+```
+
+### See also
+
+[create sprite](/reference/game/create-sprite)