Added hidden property to hyperloop js object

Updated spec.
Essentially adds a hidden property to the hyperloop module, this is helpful when trying to distinguish this hyperloop object from a kroll object when building a hyperloop module for ti.curent

This PR goes along with [Hyperloop-common](https://github.com/appcelerator/hyperloop-common/pull/65) and [Titanium Mobile](https://github.com/appcelerator/titanium_mobile/pull/5914)