[Docker API] Create pipe to pass Rspamd UI worker password
[Dovecot] Pull Spamassassin ruleset to be read by Rspamd (MANY THANKS to Peer Heinlein!)
[Dovecot] Garbage collector for deleted maildirs (set keep time via MAILDIR_GC_TIME which defaults to 1440 minutes)
[Web] Flush memcached after mailbox item changes, fixes#1808
[Web] Fix duplicate IDs, fixes#1792
[Compose] Use SQL sockets
[PHP-FPM] Update APCu and Redis libs
[Dovecot] Encrypt maildir with global key pair in crypt-vol-1 (BACKUP!), also fixes#1791
[Web] Fix deletion of spam aliases
[Helper] Add "crypt" to backup script
[Helper] Override file for external SQL socket (not supported!)
[Compose] New images for Rspamd, PHP-FPM, SOGo, Dovecot, Docker API, Watchdog, ACME, Postfix
Some older versions of docker need specific version of client api to be able to
communicate. This change allows automatically detect and set version of API to
match server version of API.
Fixes#765
