SegmentEnumerable

Wrapper around [SegmentIterator](API\Runtime\GeometryCore\TPolygon2\SegmentIterator) that has [begin()](API\Runtime\GeometryCore\TPolygon2\SegmentEnumerable\begin) and [end()](API\Runtime\GeometryCore\TPolygon2\SegmentEnumerable\end) suitable for range-based for loop