* Add support for auto-detection of featured images.

* Rename Partial, Add Documentation

Renamed the partial to func/GetFeaturedImage.html.

Additionally added more documentation in the partial to explain how it
worked, and what values were returned.

Co-authored-by: Sean Zimmermann <sz2243@columbia.edu>

* Create fr.toml

French translation

* Social link to "mastodon" added

* Some statics partials are cached, to optimise rendering

* Caching moved so that the i18n menu will work as expected. Refs #35

* Create fr.toml

French translation

* Social link to "mastodon" added

* Some statics partials are cached, to optimise rendering

I updated the documentaiton as well as changed the contact page in the
exampleSite to use this feature as a demo.