Added unit tests to features implemented in v0.1.0

This pull request is in reference to Issue #2
[Mocha](http://visionmedia.github.io/mocha/) testing framework is used to write the tests. To run the tests, go to the project directory and execute ```npm test```. In future, unit tests are to be written for each new feature (Separate unit tests for separate modules), and every commit should pass the existing tests before being considered for merging.