Improve page titles

[fhennig]

Currently the page titles are just "

:: Stackable Documentation", for example for Druid > Getting Started > Installation it's
Installation :: Stackable Documentation.

This is not as helpful an leads to confusion, as all operators have i.e. an install page and you cannot distinguish them based on the title.

Google also doesn't like this (SEO).

The module and component of the page are available to the UI template and can be incorporated into the page title.

https://docs.antora.org/antora-ui-default/templates/

I think "<document title> :: <module> :: <component> :: Stackable Documentation" makes sense

[fhennig]

Merged into the docs here: stackabletech/documentation#385