Added colorized output for the Node.js example

* Added `colors.js` into dependencies
* Updated documentation
* Added ANSI colorization into the console output

(The downside is the script now depends on `colors.js`, the upside is it looks nicer :)

![colorize](https://f.cloud.github.com/assets/4790/204574/ea943cf0-817f-11e2-8ddb-f1c619a1beb9.png)