[Paraview] Adding functionality to the apply event

[cunrein]

Hello List,

In a [much much] older version of ParaView, I have a working 
filter/objectPanel pair that inherits from pqAutoGeneratedObjectPanel 
and overloads the accept method.  I want to update this to work with 
PV4.3.  ObjectPanels have been replaced with the PropertyPanel.  Do I 
want to inherit from pqPropertyPanel and overload the apply method?  If 
so, is there a CMake macro to add this?  It doesn't look like 
ADD_PARAVIEW_OBJECT_PANEL will work with the new panel philosophy.  If 
creating a new panel is not the right thing to do anymore, how do I add 
functionality to the apply event?

Thanks, Chris