This adds an optional eurooffice instance to the recipe. Contrary to the
OnlyOffice integration, which is a separate recipe, I choose this way
because I suppose that most of the time the eurooffice instance will
only be used by Nextcloud.
There seems to be an error with the current EuroOffice official image
which fails to initialize their database. For this reason it also includes
a Postgres and a RabbitMQ service. Both are initialised upon first
usage.
Linus Gasser