#curl switches IRC network to libera.chat

[Daniel Stenberg via curl-library]

Hi team!

Due to turbulence on Freenode [1][2], we follow our friends and we are setting
up our new camp on the https://libera.chat/ network.

The same channel name (#curl), same rules, mostly the same people.

Follow along, talk curl and related topics in a relaxed atmosphere. As much as
you want. Or just idle and chill.

The docs is also updated accordingly: https://curl.se/docs/irc.html

[1] =
https://www.vice.com/en/article/m7ev8y/freenode-open-source-korea-crown-prince-takeover
[2] =
https://boingboing.net/2021/05/19/freenode-irc-staff-quit-after-new-owner-seizes-control.html