Use InfraRed's version of OnlyOffice

Somebody from InfraRed worked on a better Docker container for OnlyOffice:

https://0xacab.org/infrared/platform_wg/docker-onlyoffice-documentserver

Some improvements:

1. Increase the limit on number of connections.
2. Completelly remove database, Redis and RabbitMQ from the image, and outsource them to external containers.
3. Have JWT enabled by default. You need to manually set a secret key in .env, though (see "Running the application" below).
4. No SSL/TLS configuration is done here, you should use a proxy for that.

We can use the image(s) from: https://hub.docker.com/r/infrarednetwork/onlyoffice-documentserver/tags/