title: set data attributes with ajax and select2
body: <p>I'm trying setup data attributes into select2 options but without success, at this moment i have the following JS code</p>
  
  <pre><code>_properties.$localElement.select2({
      ajax: {
          url: "url",
          type: "POST",
          dataType: 'json',
          delay: 250,
          data: function (params) {
          return {
              name: params.term, // search term
              type: 1
          };
          },
          processResults: function (data) {
  
              return {
              results: $.map(data, function (item) {
                  return {
                      text: item.name,
                      source: item.source,
                      id: item.id
                  }
                  })
              };
          },
          cache: true
      },
      //define min input length
      minimumInputLength: 3,
  
  });
  </code></pre>
  
  <p>And i want setup a data-source for the selected option value.</p>