Adds Javascript NDK Bridge

This is an initial stab at a Javascript NDK bridge. It implements a few of the basic functions of the Soomla NDK. It uses AES encryption when possible to secure the local storage of store inventory.

Integration:
1. A developer includes js/SoomlaNdk.js.
2. When running Cocos2d-x via JSB (on iOS or Android), Soomla.CCSoomlaNdkBridge will be defined and everything in SoomlaNdk.js will effectively be ignored.
3. When running Cocos2d-html5, Soomla.CCSoomlaNdkBridge will be undefined and everything in SoomlaNdk.js will be used.

To use AES encryption, the developer can include CryptoJS AES from the HTML like this:
<script src="https://crypto-js.googlecode.com/svn/tags/3.1.2/build/rollups/aes.js"></script>