How can I add dropdown list to a single row in a jexcel table? 
I have managed to add dropdown list to different columns by stating the "columns" variable like this :

```js
$('#reportCD').jexcel({
  url: 'update.php',
  colWidths: [150 <?php echo $cwOut; ?>],
  colAlignments: ['left', 'left'],
  allowInsertRow: false,
  allowDeleteRow: false,
  columns: [{
    type: 'text',
    readOnly: true
  }, {
    type: 'dropdown',
    source: [{ 'id': '', 'name': 'Normal' }, { 'id': 'B', 'name': 'B' }, { 'id': 'I', 'name': 'I' }, { 'id': 'BR', 'name': 'BR' }, ]
  }],
  columnSorting: false,
  onchange: change
});
```

But I need the dropdown list to be row-based, not column-based. I cannot find any documentation about this. Any ideas?