title: DataTable does not re-draw after updating rows
body: <p>I'm using the <a href="https://datatables.net" rel="nofollow noreferrer">DataTables</a> library to create a table with extra functionality. What I'd like to achieve, is that the user can select rows and then press a button. This will call the server, do some stuff and the rows should be updated accordingly.</p>
  
  <p>However, after I'm done iterating over the rows to be changed and setting its values, re-drawing the table does not actually update its values. I update the data object, invalidate the cache and call <code>table.draw()</code>. It's very similar to the last example on <a href="https://datatables.net/reference/api/row().data()" rel="nofollow noreferrer">this page</a>.</p>
  
  <p>I have created a <strong><a href="https://jsfiddle.net/sopascnq/" rel="nofollow noreferrer">JSFiddle</a></strong> of this issue. The button updates the date objects of the selected rows and the table is re-drawn, but the data inside the table is not updated. The core JS code:</p>
  
  <pre><code>$('#updateRow').click(function() {
      //Get the table
      var table = $('#example').DataTable();
      //Iterate over selected rows
      var rowData = table.rows({
          selected: true
      }).every(function() {
          //For every selected row, update startDate
          var d = this.data();
          d.startDate = "01/01/2017";
          console.log('Set startDate of ' + d.name + ' to ' + d.startDate);
          //Invalidate the cache
          this.invalidate();
      });
      //Re-draw the table
      table.draw();
  });
  </code></pre>