[utils] Backport traverse_obj (etc) from yt-dlp#31156

Merged

dirkf merged 16 commits intoytdl-org:masterfrom lebdron:feat/port-traverse-obj

Nov 3, 2022

+662

Commits on Aug 10, 2022

[utils] Backport traverse_obj from yt-dlp
lebdron
committed

Commits on Aug 12, 2022

[utils] add helper functions and Nonlocal to traverse_obj, use compat_str
lebdron
committed

Commits on Nov 1, 2022

Add tests for Unicode case folding support matching Py3.5+
dirkf
authored

Commits on Nov 2, 2022