[Courier-imap] New releases of courier, courier-imap, maildrop, and cone packages

[Sam V. <mr...@co...>]

Download: http://www.courier-mta.org/download.html

Changes:

- courier: the SMTP sending code has been rewritten and factored out into an  
internal library.

- courier: new "verifyfilter" module, a filter module that verifies the  
email sender address by initiating a callback connection to the sender's  
domain, using the internal SMTP library. The module is also available as a  
"verifysmtp" command-line tool, that does the same.

- maildrop: added the new "system" command.

- courier, courier-imap, cone: OpenSSL 1.1.0 update. Some options to select  
specific TLS protocol levels are no longer available. The TLS_PROTOCOL  
setting adjusted accordingly, and the deprecated options are mapped to their  
nearest approximate setting. No changes to the GnuTLS alternative option.