Log notice-level message for > 1 consecutive unique login attempts

The log format and details might need some adjustment, but this is a start.

Also, don't delay 3 seconds before disconnecting socket when mail server has
reached maximum number of clients - we should immediately release resources
(the socket) and be able to accept another connection ASAP instead.

Deal with new CID 470557 and 470554 in mail server: resource (file*)
leaks in error paths (corner case).

Set minimum severity of TLS messages in web sever to INFO. Debug-level would
hide some common TLS session errors.