terminal: WriteTerminalTitle to terminal not stdout

The terminal title output should go to the same place as the rest of the
terminal output.  It's important _not_ to send it to stdout, where it
would get included with the main program output when redirected to a
file - for instance with the rclone cat command.

lib/terminal/terminal_normal.go

@@ -34,5 +34,5 @@ func ReadPassword(fd int) ([]byte, error) {
 
 // WriteTerminalTitle writes a string to the terminal title
 func WriteTerminalTitle(title string) {
-	fmt.Printf(ChangeTitle + title + BEL)
+	fmt.Fprintf(TerminalOutput, ChangeTitle + title + BEL)
 }