Major touchup

* Added docblocks
* Added namespace
* Improved composer configuration
* Streamlined the API (BC Breaks).
* Refactored code for more readability
* Added adapters. Guzzle as client is now interchangeable.
* Added request and response filters. Users can now modify the Symfony requests and responses to their liking.
@omares, very true. Either we go for a nice way of using the class, or go for nice code :)