BUG: #3262 update data probe on non-mouse-move events

Allow key strokes and other events that change the slice display
to trigger updates to the DataProbe window.  Only update the display
for the sliceView that matches the one most recently entered by
the mouse pointer.

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22253 3bd1e089-480b-0410-8dfb-8563597acbee