Enable roundcube shell scripts to be directly executed

[lukasmu]

In my Kubernetes cluster I want to define a CronJob resource for periodic database cleanup as described here.

Ideally, I would like to do this by passing "bin/cleandb.sh" as argument to the entrypoint. See example in the commits.
Currently, this does not work since roundcube is not been copied to the docroot when the first argument passed to the entrypoint does not start with apache2 or php-fpm.

So I propose to extend the condition in all variants of the entrypoint script.

[williamdes]

@thomascube could we have this one?

[thomascube]

Seems fair enough.

Although the cleanup cron job could also open a terminal into a running Roundcube pod and execute the cleanup command there. However, the changes makes sense to me.