Merge topic 'orthographic_view_extras'

5ef53b74 Bring back vtkSITimeLabelProperty.
4d642fac Add interaction support to vtkPVOrthographicSliceView.
Merge master into next

* commit 'aa525d5d662ea6c7036e47a07e4c8a146a773e5f':

Change-Id: Ie4d3cd2094302e8c2d81eb76be78821c51bee9fb