ENH: Update selected Filters/Core to support DesiredOutputPrecision

This updates a first batch of core filters to support a choice of
desired precision (default, single, or double) for output points. It
uses the analogous code in vtkThreshold as a model.

Change-Id: I4fadc768f1b4f5ade69445840ae8b0a8c820bc3b
Merge topic 'filters-core-desired-output-precision-1' into master

767de425 ENH: Update selected Filters/Core to support DesiredOutputPrecision