Update error page navigation

- [fix] remove the "all sections" link, that was pointing to a page that no longer exists
- [fix] update navigation to the latest UK navigation (in lowercase)
- [new] nav links: remove that weird effect on click that was hiding the text
- [fix] point to the correct feedback form in the footer
- [fix] indentation and syntax tweaks

![ ](http://gifs.joelglovier.com/high-five/police-high-five.gif)
This should be an apostrophe.