Refactor configuration to a more Ruby way.

Class variables (@@) are very rarely used within Ruby. It's an odd
situation with the singleton pattern, but I think the method I've used
here is an improvement. Happy for debate though :)
Fix travis.yml for code climate
Merge pull request #12 from iHiD/refactor_config

Refactor configuration to a more Ruby way.
Merge pull request #13 from iHiD/travis

Fix travis.yml for code climate