Builtin Prosody compatible with docker

[JohnXLivingston]

Make the builtin Prosody work with docker installations, and make the corresponding documentation.

[JohnXLivingston]

Should be ok: https://framacolibri.org/t/peertube-plugin-livechat-v1-0-1-is-out/11140/11?

Only one thing to fix: the Prosody process is running twice. I need to find how to prevent the system to start the process automatically.

[JohnXLivingston]

Note for myself, try this:

https://askubuntu.com/questions/779554/how-to-install-apt-package-without-starting-systemd-process

apt-get download prosody
sudo dpkg --unpack prosody.deb

[JohnXLivingston]

Or this: https://major.io/2016/05/05/preventing-ubuntu-16-04-starting-daemons-package-installed/

ln -s /dev/null /etc/systemd/system/prosody.service

(before installing prosody)

[JohnXLivingston]

Done, and will be simplier with v6.