Created sampleProblem.js file

Created sampleProblem.js file which contains all of the info we should need about a problem in order to be able to serve it to a user, and test it. Added chai to the package.json. Running 'mocha sampleProblem.js' will run the tests if you are interested in using it that way, but the tests are really intended to be pulled out of the sampleProblem.js file and into its own file where it will be run once the users function has been evaluated.