fix missing last log line

Sometimes calls to app.err.Fatalf would fail to print the error to the
console, and fail to show "A crash report has been saves to...". Both of
these should be fixed now.

main.go

@@ -98,7 +98,7 @@ type appContext struct {
 	telegram         *TelegramDaemon
 	discord          *DiscordDaemon
 	matrix           *MatrixDaemon
-	info, debug, err logger.Logger
+	info, debug, err *logger.Logger
 	host             string
 	port             int
 	version          string
@@ -234,7 +234,7 @@ func start(asDaemon, firstCall bool) {
 	if debugMode {
 		app.debug = logger.NewLogger(os.Stdout, "[DEBUG] ", log.Ltime|log.Lshortfile, color.FgYellow)
 	} else {
-		app.debug = logger.EmptyLogger(false)
+		app.debug = logger.NewEmptyLogger()
 	}
 	if *PPROF {
 		app.info.Print(warning("\n\nWARNING: Don't use pprof in production.\n\n"))