A lots of updates related to the test suite.

* Add minitest as test framework of the gem
* Add VCR to record the request answers
* Add Turn to pretify our output
* Update the Rake Task test to load minitests suite
* Change the way the leetchi key is loaded. It now use a path instead
of the key itself.
* Moved the resources outside of the resource folder. For better
architecture.

Still got to write some tests on the new features.

Ref: #3 #4 #6