minor #11329 [Cache] Show how to configure the cache (Nyholm)

This PR was submitted for the master branch but it was squashed and merged into the 3.4 branch instead (closes #11329).

Discussion
----------

[Cache] Show how to configure the cache

This will fix #10989, fix #8711 and resolve many of my previous headaches.

I want to have a page that explain how you configure the cache with the framework bundle. I added a first draft, some things are just notes to myself.

This is clearly a work in progress, I will continue on this tomorrow.

#eu-fossa

Commits
-------

957fbab [Cache] Show how to configure the cache

Author: wouterj