ENH: add an event type for the end of a fiducial interaction

This can be used to trigger execution at the end of the interaction
instead of doing it on every mouse move.

git-svn-id: http://svn.slicer.org/Slicer4/trunk@23368 3bd1e089-480b-0410-8dfb-8563597acbee
ENH: update to new LandmarkRegistration

Makes use of the new fiducial end moving event

git-svn-id: http://svn.slicer.org/Slicer4/trunk@23369 3bd1e089-480b-0410-8dfb-8563597acbee