add config ALLOW_ADMIN_EMAIL_LOGIN and implement password-less SOGo login admins

generate_config.sh

@@ -200,6 +200,10 @@ SOLR_HEAP=1024
 
 USE_WATCHDOG=n
 
+# Allow admins to log into SOGo as email user (without any password)
+
+ALLOW_ADMIN_EMAIL_LOGIN=n
+
 # Send notifications by mail (no DKIM signature, sent from watchdog@MAILCOW_HOSTNAME)
 # Can by multiple rcpts, NO quotation marks