Support aliased mail fetching
Move new ticket settings away from mail account section
Ensure that the message has a message-id

And ensure that the email address is trimmed to help matching against email
registered for previous tickets.
Ensure no leading or trailing whitespace on the remote_addr

If reading the remote_addr from X-Forwarded-For header, ensure that there is
no leading or trailing whitespace. If ip_binding is enabled for staff
sessions, this could cause unnecessary logouts