No Category Parents

This plugin completely removes the mandatory ‘Category Base’ and all the parents from your
category permalinks (e.g. /category/parent-category/my-category/ becomes /my-category/).

It also shortens post permalinks when you use the /%category%/ permastruct, so a post filed
under a deeply nested category still gets a short URL.

If a post or page already uses the same slug as a category, the post keeps the clean URL and
the category is served from /my-category-cat/ instead.