Default config breaks Polychat when run with Docker

[ThePixelbrain]

The IP address for Ssmp (Polychat) is set to 127.0.0.1 in appsetings.default.json.

This should be changed to 0.0.0.0, otherwise it won't be exposed when running inside a docker container.

Without changing this, the integrated Polychat server won't run properly inside docker.

I can make a quick PR for this, no idea if this project is actually being maintained anymore.