Refactor PointSet Interaction plugin to use the new node selection widgets
Some refactoring / re-design has been done as a first step.
After that a single node selection widget has been added that accepts data nodes of type PointSet.
Test Plan: manual GUI test
Reviewers: floca, O3 MITK Reviewer Group II
Reviewed By: floca, O3 MITK Reviewer Group II
Subscribers: kalali, floca
Differential Revision: https://phabricator.mitk.org/D328