This also updates validation tasks and documentation, pointing to
variables in the matrix-synapse role which don't currently exist yet
(e.g. `matrix_synapse_container_labels_client_synapse_admin_api_enabled`).
These variables will be added soon, as Traefik labels are added to the
`matrix-synapse` role. At that point, the `matrix-synapse-reverse-proxy-companion` role
will be updated to also use them.
* Add example configuration for Caddy v2
Add a basic example how to get synapse-admin running behind Caddy v2 proxy.
* Improve working, fix typos
* Fix typos
Co-authored-by: Slavi Pantaleev <slavi@devture.com>
