Enable more help topics for game API.

docs/reference/game/is-touching.md

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+# Touching
+
+Find whether the sprite is touching another sprite you say.
+
+Sprites are touching if they share the same LED.
+
+```sig
+let item: game.LedSprite = null;
+item.isTouching(null);
+```
+
+### Parameters
+
+* a **sprite** you are checking
+* another **sprite** that might be touching the one you are checking
+
+### Returns
+
+`true` if the two sprites are touching.
+
+### Example
+
+This program creates two sprites called ``matter`` and ``antimatter``,
+and then checks whether they are touching.  If they are, there is an
+explosion.
+
+```blocks
+let matter = game.createSprite(2, 2);
+let antimatter = game.createSprite(2, 2);
+if (matter.isTouching(antimatter)) {
+    basic.pause(500);
+    basic.clearScreen();
+    basic.showString("BOOM!");
+}
+```
+
+### See also
+
+[create sprite](/reference/game/create-sprite),
+[touching edge](/reference/game/touching-edge),
+[if on edge, bounce](/reference/game/if-on-edge-bounce)