login proxy: Added delayed disconnection of clients on server mass-disconnect. login_proxy_max_disconnect_delay setting (default 0 = disabled) controls for how long time period the disconnections are spread to. The idea behind this is to avoid load spikes due to client reconnections when a backend server dies or is restarted.

Changed type of internet port values to in_port_t everywhere. Created special SET_IN_PORT setting type for internet port values. Created net_str2port() for parsing internet port values. Removed several atoi() invocations in the process.

login-proxy: Don't crash if connect() succeeds but login fails with timeout.

login proxy: If passdb returns proxy_refresh=<secs>, send username to proxy-notify fifo every n secs. --HG-- branch : HEAD

imap/pop3 proxy: Track "destination down" state separately for IP+ports, not just IPs. In some systems different ports could get redirected to different servers. --HG-- branch : HEAD

Compiling fix. --HG-- branch : HEAD

login proxy: And added new files missing from previous commit. --HG-- branch : HEAD