[READY] Packaging

It makes Imager installable through `npm` and `bower`:

```bash
npm install imager
// -> available as `node_modules/imager/Imager.js

bower install imager
// -> available as `bower_components/imager/Imager.js`
```

To be merged when:

- [ ] major parts of the refactoring are okay (constructor, `data-src` API etc.)
- [ ] README is updated
- [ ] we are ready to say it's production ready

![](http://i.imgur.com/JYFDWDz.gif)