Create documentation overview with all possible settings

[tyll]

https://github.com/linux-system-roles/network/blob/main/scripts/print_all_options.py allows to create an overview of all settings the role accepts. Use this to create an overview (maybe in the appendix) of the documentation and integrate this into the CI to ensure that it is up to date. Ideally, the settings from the script would link to the part of the README that explains how to configure the setting.