We want to avoid deadlock situations and right now if there is a process
running with the same PID that is not our process (e.g. after a reboot)
we might be waiting forever to run the cron again. So to make this
transparent to the user, we at least post a warning into the logfile.

- use clientdb config for addon sql files

- fixes in addon installer

- do not install/update addons during install/update of ISPconfig. This only leads to lots of trouble

- do not install/update addons during install/update of ISPconfig. This only leads to lots of trouble

- TODO: the server services plugin is not capable of enabling and disabling addon plugins, yet

- improved rspamd handling

- changed some rspamd config to new syntax