return selected time value to selectTime event callback

This takes care of my suggestion: https://github.com/jonthornton/jquery-timepicker/issues/302

Goes good with the "Non-input Example".

Usage:
```
$(".non-input-with-picker").timepicker();
$(".non-input-with-picker").on("click", function() {
    $(this).timepicker("show");
});
$(".non-input-with-picker").on("selectTime", function(event, selectedTime) {
    // do stuff with selectedTime (ex: "1:30pm")
});
```