+ Refactor all but the ParaView-specific pieces from
  the SMTK resource panel widget into a new class named
  qtResourceBrowser.
+ Remove the unimplemented search text entry from the
  resource panel.
+ Add methods to qtSMTKUtilities to accept an override for
  the QTreeView widget.
+ Moves synchronization of the SMTK selection (when resources
  rather than components are selected) with ParaView's
  pipeline inspector into a new behavior named
  pqSMTKPipelineSelectionBehavior.
+ Fix the `Selection::visitSelection()` method; it
  was not possible to call the more general visitor
  because shared pointers can be implicitly converted.
+ Add a `relatedObject()` method to descriptive phrases
  and phrase content. Arguably, this should replace
  `relatedComponent()` and `relatedResource()` as the
  only method they provide.