Added JavaScript with Mocha + Chai + Sinon

This pull request adds Mocha test framework, with Chai assertion library, and Sinon for mocking, spys, and stubs. I have no experience with Docker or Ruby, so I'm kinda hoping you can help me if this is all horribly wrong in some way. Also, I'm not sure about how the Docker non-global node modules will work. If npm install is executed by the Docker stuff in the same directory that the hikerTest.js winds up, it should be ok. Thanks for CyberDojo. It's awesome!