Kohana 3.3 compatibility; merge forks & add Apache-2 license

* Update filenames for PSR-0
* Added relation() function to return relation info
* Changed enum field behavior
* Prevent loading of a single document/model if no search criteria is set
* Fix: Use MongoClient instead deprecated Mongo
* Remove defined('SYSPATH') check; place your modules outside public dir!
* Config files to lowercase (mangodb.php and mangocti.php)
* Add CHANGELOG.md and LICENSE.TXT
* License under Apache-2.0 (Compatible with Beerware; same as MongoDB driver)
* Original license/copyright included