update docs

docs/20_Installation.md

-## Start from scratch
+## First steps
+
+This project contains files for docker, the docs and webroot with a demo of implemented components.
+To bring up and running:
+
+You need 
+
+* a rootless docker instance (if it is working with docker as root I didn't tested).
+* docker compose
+* facl
+
+Steps:
+
+* start ./docker/init.sh
+* press ``i`` to apply write permissions with setfacl command
+* press ``u`` to startup the container
+
+In your browser open http://localhost:8008/.
+
+## Start a new project using demo page
+
+Steps:
+
+* delete the directories .git + docs
+* delete the files .gitignore + readme.md
+
+## Start from scratch (WIP)
 
 If you have no AdminLTE page and want to jump in from point zero: