Get public LAN IP address of orchestrator automatically

[trkks]

For accessing the orchestrator (index-page or packages etc) the available address in LAN-setup is gotten from an environment variable which means in order to set it up one needs to either:

A)
1. Start up the container and while it is running, check the container for ip address X e.g. with sudo docker container inspect <container>
2. Shut down the container, set environment variable PUBLIC_HOST=http://<X>
3. Start up the container again with the available address now set

B) Guess what public IP-address X the container will be assigned to in advance, saving from the trouble of starting it up twice