more styling for disabled options

new "Developer" tab (by default all options are disabled, users can't modify them)
fixed UserprefsDisallow export in setup script

setup/scripts.js

@@ -183,6 +183,9 @@ $(function() {
            return;
        }
        var el = $(this).find('input');
+       if (el.attr('disabled')) {
+           return;
+       }
        el.attr('checked', !el.attr('checked'));
    });
 });