Merge topic 'remove_obsolete_panels'

7a749789 Hide ShowBounds on Extract Selection panel.
79adb438 Remove obsolete pqRubberBandHelper.
ab02ba45 Add deprecation comments.
096974ec Fix PassArrays Properties panel.
6a1b11f9 Remove obsolete pqProxyPanel subclasses.
Merge topic 'rms-plots'

5910af77 Add GetLabel for vtkXYChartRepresentation
0a09d3e6 Derive pqFontPropertyWidget from pqPropertyGroupWidget.
Merge master into next

* commit 'aa525d5d662ea6c7036e47a07e4c8a146a773e5f':

Change-Id: I7f848c56df30f1d0a7750c8ea5013662ad60ce07