Qsmtp-0.27: Qsmtp version 0.27

• Qsmtpd: the spffriends files are no longer a list of host names, but ipbl format files
• Qsmtpd: authentication using TLS certificates now also looks at the common name field, allowing not only single users but also whole hosts to be authenticated for relaying
• Qsmtpd: TLS authentication code is now enabled
• Qsmtpd: fix and add some enhanced status codes
• Qsmtpd: add stricter checking in CRAM-MD5 authentication before passing the input to the backend
• Qremote: the file outgoingip6 may now hold an IP address used to bind to when sending mail via IPv6
• Qremote: prefer IPv6 addresses over IPv4 ones if both have the same MX priority
• Qsurvey: several improvements, e.g. IPv6 support and symlinking from domain names to IP address directories
• Qsurvey now depends on the availability of the openat() syscall
• much of the AUTH and userbackend has been refactored