Added missing class desc

Author: photonstorm

src/physics/matter-js/index.js

@@ -72,3 +72,12 @@ module.exports = {
  *
  * @class MatterJS.Engine
  */
+
+/**
+ * @classdesc
+* The `Matter.Vertices` module contains methods for creating and manipulating sets of vertices.
+* A set of vertices is an array of `Matter.Vector` with additional indexing properties inserted by `Vertices.create`.
+* A `Matter.Body` maintains a set of vertices to represent the shape of the object (its convex hull).
+*
+* @class MatterJS.Vertices
+*/