fix issue #12. The StopWord validation is working.

Commit changelog:

 * The class StopWords has been created.
 * Clean some unused imports.
 * Clean some confused code.
 * Create some constructors methods.
 * Create AppSetup class. It'll be use for setup parameters for global use in the app.
 * Add some comments in the methods and class.
Merge pull request #16 from tomasdelvechio/iss12

fix issue #12. The StopWord validation is working.