Fix case-sensitivity in OS.Path A missing "not" meant that case-sensitivity was reversed between Windows and Unix.
Fix case-sensitivity in OS.Path
A missing "not" meant that case-sensitivity was reversed between Windows and Unix.

dcjm/polyml,polyml/polyml,dcjm/polyml,dcjm/polyml,dcjm/polyml,polyml/polyml,polyml/polyml,polyml/polyml