Refresh screen when exiting WeeChat (to display messages printed after /quit)

src/core/wee-command.c

@@ -3471,6 +3471,7 @@ command_upgrade (void *data, struct t_gui_buffer *buffer,
     exec_args[3] = strdup (weechat_home);
     
     weechat_quit = 1;
+    weechat_upgrading = 1;
     
     /* save layout, unload plugins, save config, then upgrade */
     gui_layout_save_on_exit ();