MongoDB support. WIP

It's a complete class replacement for Mango Reader module.

   __Warning: TEMPORARY DO NOT USE Mango Reader module!__

This class will be used to for full access to the sessions, logs, and other data to improve performance. I have provided a detailed description of the class in the form of PHPDoc comments. __Please read them initially__

Todo:
+ Mango_Collection
+ Mango_Document
+ GridFS support
+ Log Reader/Writer
+ Session Reader/Writer
+ Cache Reader/Writer