Update use of magic API
Update dependencies
Various UI improvements

* Fluid layout for small resolutions using a bootstap 3-style grid (fixes #38)
* Mobile first: desktop extends mobile, not the other way round
* Fixed the image resizer on Chrome on iOS
* Tap on a resized image to switch mode: screen width, 1:1 or retina
* Hide mark page as read button if page === all
* sticky-footer now just works with no manual touch-up