This is an attempt at optimizing service startup.
The effect is most pronounced when many services are restarted one by one.
The systemd service manager role sometimes does this - for example when `just install-service synapse` runs.
In such cases, a 5-second delay for each Synapse worker service
(or other bridge/bot service that waits on the homeserver) quickly adds up to a lot.
When services are all stopped fully and then started, the effect is not so pronounced, because
`matrix-synapse.service` starts first and pulls all worker services (defined as `Wants=` for it).
Later on, when the systemd service manager role "starts" these worker services, they're started already.
Even if they had a 5-second wait each, it would have happened in parallel.
* Allow the mautrix whatsapp relaybot to be enable with a variable
This allows a user to enable the relaybot by setting a variable in
`vars.yml` in the same way that the mautrix signal relaybot is
configured.
* Correct default values for mautrix whatsapp relaybot variables
* Add documentation for using the relaybot with mautrix whatsapp
* Adjust variable names to better reflect what they do
* Set default variables properly and use to_json in template
