adding documentation to some files with only one [description] tag

src/actions/RotateAround.js

@@ -8,10 +8,11 @@ var RotateAroundDistance = require('../math/RotateAroundDistance');
 var DistanceBetween = require('../math/distance/DistanceBetween');
 
 /**
- * [description]
+ * Rotates each item around the given point by the given angle.
  *
  * @function Phaser.Actions.RotateAround
  * @since 3.0.0
+ * @see Phaser.Math.RotateAroundDistance
  *
  * @generic {Phaser.GameObjects.GameObject[]} G - [items,$return]
  *

src/actions/Shuffle.js

@@ -7,10 +7,11 @@
 var ArrayShuffle = require('../utils/array/Shuffle');
 
 /**
- * [description]
+ * Shuffles the array in place. The shuffled array is both modified and returned.
  *
  * @function Phaser.Actions.Shuffle
  * @since 3.0.0
+ * @see Phaser.Utils.Array.Shuffle
  *
  * @generic {Phaser.GameObjects.GameObject[]} G - [items,$return]
  *

src/boot/Game.js

@@ -154,7 +154,7 @@ var Game = new Class({
         this.cache = new CacheManager(this);
 
         /**
-         * [description]
+         * An instance of the Data Manager
          *
          * @name Phaser.Game#registry
          * @type {Phaser.Data.DataManager}

src/dom/AddToDOM.js

@@ -13,7 +13,7 @@
  *
  * @param {HTMLElement} element - The element to be added to the DOM. Usually a Canvas object.
  * @param {(string|HTMLElement)} [parent] - The parent in which to add the element. Can be a string which is passed to `getElementById` or an actual DOM object.
- * @param {boolean} [overflowHidden=true] - [description]
+ * @param {boolean} [overflowHidden=true] - Whether or not to hide overflowing content inside the parent.
  *
  * @return {HTMLElement} The element that was added to the DOM.
  */

src/gameobjects/GameObject.js

@@ -195,10 +195,11 @@ var GameObject = new Class({
     },
 
     /**
-     * [description]
+     * Adds a DataManager to this object.
      *
      * @method Phaser.GameObjects.GameObject#setDataEnabled
      * @since 3.0.0
+     * @see Phaser.Data.DataManager
      *
      * @return {Phaser.GameObjects.GameObject} This GameObject.
      */