Lots more physics tests and updates.

PLEASE DO NOT upgrade to this release if you need your game working and it uses any of the physics functions, as they're nearly all broken here.
Just pushing up so I can share it with someone.

src/utils/Utils.js

@@ -75,6 +75,18 @@ Phaser.Utils = {
 
     },
 
+    /**
+    * Returns true if the object is an Array, otherwise false.
+    * @method Phaser.Utils.isArray
+    * @param {object} obj - The object to inspect.
+    * @return {boolean} - true if the object is an array, otherwise false.
+    */
+    isArray: function (obj) {
+
+        return toString.call(obj) === "[object Array]";
+
+    },
+
     /**
     * This is a slightly modified version of jQuery.isPlainObject. A plain object is an object whose internal class property is [object Object].
     * @method Phaser.Utils.isPlainObject