Issue of filter_functions on Exact match when slow-typing

[victorshengchen]

The filter was applied on the previous results when user had slow-typing
To reproduce the issue, in docs/example-widget-filter-custom.html, I've added below function in js:
3 : function(e, n, f, i, $r, c, data) { return e === f; },
and added a new row at the end of the table by:
<tr> <td>John</td> <td>Hood</td> <td>Fort Worth</td> <td>1</td> <td>$22.09</td> <td>17%</td> <td>Jun 11, 2011 10:55 AM</td> </tr>
When you type in '1' and '3' slowly in the filter input of column Age, no result will respond, which is not as expected

[victorshengchen]

@Mottie could you help on this issue? Thanks.