Clipper: Clean up leftovers
Remove support for non-quad polygons from clipper and don't expose general purpose clipping routine in header.
These changes were mentioned as nice to have in previous vertex clipping MRs a few months ago.
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Remove support for non-quad polygons from clipper and don't expose general purpose clipping routine in header.
These changes were mentioned as nice to have in previous vertex clipping MRs a few months ago.