Disable GUI about docker-jdownloader-2

[jlesage]

This is something that will eventually be possible.

However, if you want to prevent access to the UI right now, you just need to not map port 5800 (assuming your are using the default bridge network mode).

[Somebody25]

Alright, that worked. I was just a little bit confused because the port is declared as mandatory and I was afraid that the server wouldn't work at all but it does. Thanks!