[docs] [issue22014] Add summary table for OS exception <-> errno mapping

Jon Poler added the comment: I will give this a shot if it is just hard-coding a table with errno names. Dynamically scraping the errno names and inserting them with the exception hierarchy might be beyond me since I've never used Sphinx before. ---------- nosy: +jon.poler _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue22014> _______________________________________