Remove PyCXX from _path_in_path()
Remove PyCXX from _clip_path_to_rect()
Remove PyCXX from _affine_transform()
Remove PyCXX from _count_bboxes_overlapping_bbox()
PyList_SetItem() -> PyList_SET_ITEM() (cannot fail)
Remove PyCXX from _path_intersects_path()
Remove PyCXX from _convert_path_to_polygons()
_path.cpp: Fix multiple memory leaks