the HasConvergence mixin runs a state machine to determine
when the value has reached target from parameters 'tolerance',
'settling_time' or detects convergence failure depending on
the parameter 'timeout'.
Change-Id: Iccc3d43bcf5ab54ae02ce3a81423c2decc1b392d
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/27967
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>
