Strategies, URL variables and Unit Testing

# tl;dr

Heavy documentation and logic splitting. We can plug several way to replace the `<div>` container.

# New Stuff

* configurable URL patterns to let people use whatever file organisation for their resized images (like `http://myserver.co.uk/images/{width}-hidpi/picture.jpg`)
* configurable delay to postpone width URL calculation
* multi instance to target different part of the screen with different settings (sidebar and main content for example)
* you can plug it on any even system (DOM Events, pubsub libraries)
* ability to update the instance's pool of watched elements
* tests

# Removed Stuff

Basically, they are all about opinionated software design:

* internal event listeners (it's now the business of the people using it in their app — See the [Demo page](https://github.com/oncletom/Imager.js/blob/feature-separation/Demo/index.html#L42-43) or the [README](https://github.com/oncletom/Imager.js/blob/feature-separation/README.md) to read about how to plug on events)
* `$` shim (we just iterate on array-like of elements)

![](http://i.imgur.com/nLXxLFm.gif)
^ *responsive images huh?*