[Modules] Logging activity

[Xavier D. <xav...@gm...>]

Dear All,

The ability to log module command activity will be available out of
the box starting version 5.5. This feature relies on two new
configuration options:

* logger: the command run to transmit messages to the log system
* logged_events: list of module event to log

See details and examples at:

https://modules.readthedocs.io/en/latest/MIGRATING.html#logging-activity

Regards,
Xavier