Gruntify all the things

Use Grunt.js for building this library. The basic tasks work:
- compiling le CoffeeScript
- creating minified version
- JSHint and CoffeeLint source files and Gruntfile.js

There is one problem with running the tests: there seems to be a problem with installing phantomjs. After a successful `npm install` and hitting `grunt test`, the error that `phantomjs` is not installed correctly occurs. This needs more investigation.

Running the tests in the browser by invoking `grunt server watch` and navigating to [http://localhost:8000/tests/](http://localhost:8000/tests/) works ...