title: Is it possible to show progress bar when upload image via Retrofit 2?
body: <p>I'am currently using <code>Retrofit 2</code> and i want to upload some photo at my server.
  I know, that older version uses <code>TypedFile</code> class for uploading. And if we want to use progress bar with it we should override <code>writeTo</code> method in <code>TypedFile</code> class.</p>
  
  <p>Is it possible to show progress when using <code>retrofit 2</code> library?</p>