Add link to all pages from fronts

![alllink](https://cloud.githubusercontent.com/assets/1001642/5128078/9dbc2234-70d0-11e4-8f63-01d7ba52f8cf.gif)

Using somewhat hairy logic to determine what the link should be.

The issue is, we currently don't make any requests to Content API when rendering a Facia front, so it's difficult to know whether the front is actually overriding a tag or section, or whether it's its own custom thing that doesn't exist in Content API to begin with.