server: -netdebug flag now controls tracing for #90

Network trace is sent to stdout, no longer part of normal debug
logging.

cmd/inbucket/main.go

@@ -59,6 +59,7 @@ func main() {
 	pidfile := flag.String("pidfile", "", "Write our PID into the specified file.")
 	logfile := flag.String("logfile", "stderr", "Write out log into the specified file.")
 	logjson := flag.Bool("logjson", false, "Logs are written in JSON format.")
+	netdebug := flag.Bool("netdebug", false, "Dump SMTP & POP3 network traffic to stdout.")
 	flag.Usage = func() {
 		fmt.Fprintln(os.Stderr, "Usage: inbucket [options]")
 		flag.PrintDefaults()
@@ -89,6 +90,10 @@ func main() {
 		fmt.Fprintf(os.Stderr, "Configuration error: %v\n", err)
 		os.Exit(1)
 	}
+	if *netdebug {
+		conf.POP3.Debug = true
+		conf.SMTP.Debug = true
+	}
 	// Setup signal handler.
 	sigChan := make(chan os.Signal, 1)
 	signal.Notify(sigChan, syscall.SIGHUP, syscall.SIGTERM, syscall.SIGINT)