Added a new widget: autoroll

I have added a few days ago a new widget, the so-called autoroll by Criteo. It should basically give an overview of what you, my readers, are otherwise reading. Not sure how it works, so have I have put it a bit lower on the page. I collects the information of other autoroll users who visit this weblog, so it might only become better when you also decide too to use it.
I will keep on monitoring it and might skip it again when it does not work.