title: Cant generate existing folder for zip (JSZip.js)
body: <p><strong>Case 1:</strong>
  I am trying to access the existing folder for zip operation, but it can't be generate it. I have tried the below code for zipping existing folder.</p>
  
  <pre><code>var zip = new JSZip();
  zip.folder("../Download/Themes");
  zip.generate();
  </code></pre>
  
  <p>Example:
  I have a folder(Themes) with files  which i want to be zip in my application.</p>
  
  <ul>
  <li>folder - Themes
  <ul>
  <li>file - css1</li>
  <li>file - css2</li>
  </ul></li>
  </ul>
  
  <p>Is it possible to generate zip file from existing folder?</p>
  
  <p><strong>Case 2:</strong>
  After generating a zip file can i get the zip file from its physical path in my application?</p>
  
  <p>Thanks in advance...</p>