... and add "MAILINDEX".
As described in #2789, this is a suggested solution. Changing UID=xx to
actually get mail with UID xx and add "MAILINDEX" to get a mail with a
special index in the mail box (old behavior). So MAILINDEX=1 gives the
first non deleted mail in the mail box.
Fixes#2789Closes#2815
As the email protocols implement SASL authentication rather than IMAP,
POP3 and SMTP specific authentication, updated the authentication
keywords to reflect this.