404 widget removal or replacement

[frostschutz]

following @borekon 's pull request #69

The original Google SEO Starter Guide recommended "Google provides a 404 widget that you can embed in your 404 page to automatically populate it with many useful features."

https://webmasters.googleblog.com/2008/08/make-your-404-pages-more-useful.html

That page now states "The described product or service is no longer available." and the widget seems to be very limited in its functionality for me (search box only when it used to have useful suggestions and direct links).

The current edition of the SEO Starter Guide also no longer has any references to that widget.

As such it seems that the fixurl.js widget should be removed or replaced altogether.