Type options of cache plugins (#8624)
* Type options of cache plugins.
* Do not change type of _timeout for now.
(cherry picked from commit 37c8560542)
Co-authored-by: Felix Fontein <felix@fontein.de>
* Move licenses to LICENSES/, run add-license.py, add LICENSES/MIT.txt.
* Replace 'Copyright:' with 'Copyright'
sed -i 's|Copyright:\(.*\)|Copyright\1|' $(rg -l 'Copyright:')
Co-authored-by: Maxwell G <gotmax@e.email>
* added utf-8 markers to all .py files in plugins/{action,cache,callback}
* added utf-8 markers to all .py files in plugins/connection
* added utf-8 markers to all .py files in plugins/doc_fragments
