detect more than one script doms. #146

function handleExternalScript () {
  var container = Docsify.dom.getNode('#main');
  var scripts = Docsify.dom.findAll(container, 'script');

  for (var i = scripts.length; i--;) {
    var script = scripts[i];
    
    if (script && script.src) {
      var newScript = document.createElement('script');
      ['src', 'async', 'defer'].forEach(function (attribute) {
        newScript[attribute] = script[attribute];
      });

      script.parentNode.insertBefore(newScript, script);
      script.parentNode.removeChild(script);
    }
  }
}