Some improvements on the code and structure

* Code style, spaces and other improvements
* All tests passing
* Bin cleaning
* test/case dir was created to maintain files for cases isolated
the best way to rename a file is with `git mv`, this way I can't even diff the changes.

btw, there's no way I would prefer to use `test/lib.index.test.js` instead of a simple `test/test.js`

Also, there's no need to move the data files to another new folder.