Removed the paragraph telling a user to visit the navigations page to learn how to build more robust navigation.
The permalink was broken since Navigation no longer exists and no other suitable substitute (closest being ./permalinks) fits the description.
In case of the GitHub example links like `<a href="https://github.com/{{ org.username }}">` with the full URL plus the variable were used, but for the Twitter example link only the `{{ author.name }}` was set as `href`.