chart views. It includes a plethora of sub commits:
* Added support for vtkQtChartSeriesOptionsModel which is a model from which the
  series options are obtained by the chart layer. Also includes concrete
  subclasses for this one.
* vtkSMProperty now has a Parent ivar which refers to the Proxy to which the
  property belongs. This was needed for the vtkSMChartingArraysInformationHelper
  to make it easy to fill up the info property with the list of available
  arrays.
* Added support to vtkSMPropertyHelper to handle setting/getting of status
  properties i.e. StringVectorProperties with first value being the array name
  (or similar) and the second (or a few more) being the value or status for that
  array. This is used to get/set the series options with ease.