title: Copy option list from dropdownlist. JQuery
body: <p>Html code</p>
  
  <pre><code>&lt;select id="dropdwon1"&gt;
   &lt;option value="1"&gt;Item1&lt;/option&gt;
   &lt;option value="2"&gt;Item2&lt;/option&gt;
   &lt;option value="3"&gt;Item3&lt;/option&gt;
  &lt;/select&gt;
  
  &lt;select id="dropdwon2"&gt;&lt;/select&gt;
  </code></pre>
  
  <p>I need copy all options from dropdown1 to dropdown2, using jQuery. Whether it is possible to copy contents simply?</p>