Fixed linking in the recipes page.

A change to compile somePage.md -> somePage/index.html leaked before it
was ready on b9341ba.

However, the recipes page still linked to somePage.html, so the links
were broken.

The links are now generated using the new friendly URLs.
Adding icons.css to base template.

This will force it to be included on all pages, and hence, show the
github icon next to the link on the header.