* sock_getln (): CtdlSockGetLine() gives us lines without \r\n, no need to look for them again
* sock_getln_err (): add integer pointer returning the actual return state in case of error
* ml_sock_gets (): use sock_getln_err () so we can abort on impropper replies
* smtp_try (): make socket nonblocking, so we can abort on error
-> we will wait 5 seconds for the remote site to send us the SMTP-State else we will abort the connection on failure.