Fix degenerate polygon removal
There was a bug in CleanGrid
when removing degenerate polygons where it
would not detect if the first and last point were the same. This has been
fixed.
There was also an error with function overloading that was causing 0D and 3D cells to enter the wrong computation for degenerate cells. This has also been fixed.
Fixes #796 (closed)
Backport: release
Edited by Kenneth Moreland