An attached property may be defined with mandatory=False.
In this case, when no value or an empty string is given,
<modobj>.<attached_mod> must return None after initialisation.
+ remove 'dispatcher' level from the logger hierarchy on modules
Change-Id: Icee3ae3f9142cd7a910c579ae1ffaa35f93cee03
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/32187
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>
