CurtainPanel.ByElement again - Issues with non-quadrilateral panels

[andydandy74]

Use case: A curtain wall that contains non-quadrilateral panels.

CurtainPanel.ByElement will return as many panels as the product of U and V subdivisions of that curtain wall, regardless of how some cells may have been merged. This only becomes obvious when applying CurtainPanel.Boundaries to the list of panels. It looks like that node will then only return PolyCurves for the first cell of a "merged" panel and null for all other cells of that panel.

Expected behaviour: Do not return any of the "subpanels", only those that actually register as panels in the Revit UI and schedules.

[andydandy74]

sample files here:
https://github.com/CAAD-RWTH/ClockworkForDynamo/tree/master/issues/4195_CurtainPanel.ByElements%20issues%20with%20non-quads