allow to define default settings on the IO class:
- a default 'port' may be given for tcp
- defaults like 'baudrate' or 'parity' might be given
for serial connections
this avoids explicit settings in the config file in case
the settings can not be changed or have a typical value
other than the defaults in serial.Serial
Change-Id: I990f47d63e785f8cc48c4af197944a8eebe91fb4
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/30555
Reviewed-by: Georg Brandl <g.brandl@fz-juelich.de>
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>