title: RestSharp DownloadData sync with progressbar
body: <p>How can I download file and show downloading progress by ProgressBar in window form app?</p>
  
  <pre><code>RestClient client = new RestClient("http://127.0.0.1/");
  
  RestRequest request = new RestRequest("/test/{FileName}");
  request.AddParameter("FileName", "testFile.abc", ParameterType.UrlSegment);
  
  string path = @"C:/Users/[user]/Desktop/testFile.abc";
  
  var fileForDownload = client.DownloadData(request);
  
  fileForDownload.SaveAs(path);
  
  if (File.Exists(@"C:/Users/[user]/Desktop/testFile.abc"))
  {
      MessageBox.Show("done");
  }
  </code></pre>
  
  <p>I write somethink like this but I don't know what now?</p>