Changed the iso8601Week function of the Datepicker interface to return type 'number', not type 'void'. See: http://api.jqueryui.com/datepicker/
RefreshHints are optional

The filters in RefreshHints should be optional so there is no error when updating a single one such as:

this.dataView.setRefreshHints({
    isFilterUnchanged: true
});
Merge pull request #1466 from styfle/patch-1

SlickGrid RefreshHints should be optional
Merge pull request #1463 from tvonclef/master

Changed the iso8601Week function of the Datepicker interface