Refactor DeformableClippingPlane plugin to use the new node selection widgets
Summary:
Clean class: reorder functions, fix style, remove comments
Use new Qt5 signal-slot syntax
Clean code: use auto, define node predicates
Modify UI to include single node selection widget
Test Plan: manual
Reviewers: floca, O1 MITK Reviewer Group I, kislinsk
Reviewed By: O1 MITK Reviewer Group I, kislinsk
Subscribers: kislinsk, floca, kalali
Maniphest Tasks: T27595
Differential Revision: https://phabricator.mitk.org/D365