Split out favicons and partials from content

[chrism]

Instead of one section which contains both

• favicons
• partials

Make each an individual item, which not only makes them easier to find in the documentation but allows for more thorough documentation for each.

For favicons maybe information from this
https://evilmartians.com/chronicles/how-to-favicon-in-2021-six-files-that-fit-most-needs

Could be useful to include