Fix hardcoded postgres template values

Upstream set mx-puppet-skype default port to 8438

matrix-appservice-slack: improved documentation

Fix to avoid putting an incorrect empty jitsi.preferredDomain when no…

Discussed in #446 (Github Pull Request).

Add global var to control skype image self build

Jitsi related firewall and port changes

Fixes an error like this:

> synapse.config._base.ConfigError: Cannot reuse as_token across application services

turn tls port update

Added Jitsi firewall ports

This will not work yet, as no version of Riot currently supports it.
It's expected to land in riot-web v1.5.16 via matrix-org/matrix-react-sdk#4348.

Initial mx-puppet-skype bridge role

Hopefully fixes an error like this (which I haven't been able to
reproduce, but..):

> [modules/xmpp/strophe.util.js] <Object.i.Strophe.log>:  Strophe: Error: Failed to construct 'RTCPeerConnection': 'matrix.DOMAIN' is not one of the supported URL schemes 'stun', 'turn' or 'turns'.

These are some new defaults that we switch to, to follow upstream
changes:

- https://github.com/jitsi/docker-jitsi-meet/commit/264df04
- 3121494d4b

Jitsi security update

We define this password in the `sip-communicator.properties`
configuration file, so this is not needed for actually running JVB.

However, it does a (useless) safety check during container startup,
and we need to make that check happy.

Co-Authored-By: Sandro <sandro.jaeckel@gmail.com>

Facebook self build

Update Caddy example in configuring-well-known to Caddy version 2

add ntpd defaults

Related to #436 (Github Pull Request).

add optional Jitsi internal auth+guests docs