(review fixes) Authentication-and-Cookies.md: behaviour changed in 0.10.0
(auth) Authentication-and-Cookies.md: provider built once, refresh_interval, aws_tokens_file, constant-time comparison (0.10.0)
(remote cookies) Authentication-and-Cookies.md: remote Cookie header built from the cookies setting (0.10.0), upgrade note, ignored-authentication warning
(wiki overhaul) Authentication-and-Cookies.md: cookies, database authentication, encryption commands