Improve examples

Since I haven't used node before, I am not sure if adding pty.js requirement is enough, or perhaps I should pull it from git to the deps directory and fiddle with the build definition? 

pty.js is not available on npm's repos, hence has to be installed via the tarbal from git lvia:
```
npm install https://github.com/chjj/pty.js/tarball/master
```