Examples: Modularize usage of cannon.js.

examples/jsm/physics/CannonPhysics.js

@@ -1,3 +1,5 @@
+import CANNON from "../libs/cannon.module.min.js";
+
 /**
  * @author mrdoob / http://mrdoob.com/
  */

examples/physics_cannon_instancing.html

@@ -12,7 +12,6 @@
 			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> physics - cannon.js instancing
 		</div>
 
-		<script src="./js/libs/cannon.js"></script>
 		<script type="module">
 
 			import * as THREE from '../build/three.module.js';