Support for jQuery 1.9 

Knockout 2.2.0 uses jQuery.clean() which is deprecated and does not exist in 1.9. 

As suggested in the [migration plugin page](https://github.com/jquery/jquery-migrate/blob/master/warnings.md#jqmigrate-jqueryclean-is-deprecated-1), you could use jQuery.parseHTML() insted of jQuery.clean() but I'm not sure of the consequences of this change.

The only line of code I can find in Knockout that uses jQuery.clean is as follows:

    var elems = jQuery['clean']([html]);