update tmux.conf.pl

tmux.conf.pl

@@ -45,6 +45,7 @@ sub set_prefs {
     # this does not workd because `run' do script asyncly
     set("base-index", "1");
     set("pane-base-index", "1");
+    set("renumber-windows", "on");
     setw("mode-keys", "vi");
     set("default-command", "/bin/bash");
     set("default-path", $ENV{"HOME"});