docs/sane.man: Move to libera.chat
Freenode.net became unacceptable for open source communities, so most of them moved to libera.chat.
#sane chat room at libera.chat already exists, so let's point sane docs there too.
Freenode.net became unacceptable for open source communities, so most of them moved to libera.chat.
#sane chat room at libera.chat already exists, so let's point sane docs there too.