title: Download multiple files with rails
body: <p>I'm currently using PRAWN with latest release of rails and I can't figure out how to download multiple files with a single HTTP request. in my controller I have the following code:</p>
  
  <pre><code>Fill PDF with my stuffs...
  PDF.render_file "foo.pdf"
  send_file("foo.pdf")
  </code></pre>
  
  <p>And it download correctly the file but - if after that - I put another istance of the same code...it will execute only the last one, foo2</p>
  
  <pre><code>PDF.render_file "foo.pdf"
  send_file("foo.pdf")
  PDF.render_file "foo.pdf"
  send_file("foo2.pdf")
  </code></pre>
  
  <p>Moreover, If at end...I wish to render another view, I can't do it. </p>
  
  <p>Question is: </p>
  
  <p>How can I download 2 different files in a single action inside controller and, finally, render a view?</p>