Fix for IE With Select Year/Month and Setting Highlighted Date

Issue can be seen here: http://jsfiddle.net/andrewburgess/Q5F6Q/ using version from 2/14/2014

Using the following instantiation:
```
$('input').pickadate({
    selectYears: 30,
    onStart: function () {
        this.set('highlight', 824330296545);
    }
});
```
Trying to change the year triggers two `change` events. The first is correct, but the second will end up turning the `selectYear` to 1900