Set up testing (grunt, jshint) and Travis CI config

Before merging this, be sure to connect your GitHub repository with Travis CI so that they are allowed to run tests for you and report the results back here.

More info: http://about.travis-ci.org/docs/user/getting-started/#Step-one%3A-Sign-in.

I've already done step three as part of this pull request, so when your'e there, merge this one instead of actually adding that file.

You can test this locally by checking out my branch (follow GitHub's instruction). Then locally run: `npm install && npm test` (assuming you have nodejs installed).