Website/Webspace Security is not well documented

[alexander-schranz]

Currently the webspace docs is linked to the https://docs.sulu.io/en/2.2/cookbook/securing-your-application.html Which in my case is a documentation about Admin security and should be more moved into a Extend Admin Security Docs.

So the Secure your application is more about:

• https://github.com/sulu/skeleton/blob/f06cda85e5d1be05ac46e9f6bda5f11fd3f6d180/config/packages/security_website.yaml#L1
• https://github.com/sulu/skeleton/blob/f06cda85e5d1be05ac46e9f6bda5f11fd3f6d180/config/webspaces/example.xml#L9 (add security here)
• https://docs.sulu.io/en/2.2/cookbook/user-context-caching.html

Also the sulu:security:init command is not documented.