title: Load values in select2 multiselect
body: <p>I'm using <code>select2</code> in place of search box.</p>
  
  <p>Here i'm using to load countries values like this</p>
  
  <pre><code>$("#countries").select2({
      multiple: true,
      tags:["India", "Japan", "Australia","Singapore"],
      tokenSeparators: [","]
  });
  </code></pre>
  
  <p>When i press save button, they are properly submitted to the server, now here the question is
  when i want to modify the country field after saving to server, how i can load the saved values to the country field.</p>
  
  <p>This is how i retrieve data from server</p>
  
  <pre><code>$.getJSON('/dataprovider?data=fetchCountriesForm', function(opts) {
  
      //the opts here contains the json values of the countries.
  
      //what code should be written here to load the values in $('#countries).select2();
  
      //user can add some more countries or can remove the previously added countries. 
  
  }
  </code></pre>