Kohl’s Department Stores announces today a collaboration with Disney on a national call for a Sing Your Heart Out campaign. Now through September 29, fans of the movie “Frozen” and aspiring singers nationwide can submit videos of themselves singing “Let it Go” for the chance to be included in a Kohl’s holiday commercial that will air during the 2014 American Music Awards (AMAs) broadcast. “The American Music Awards kick off the most important time of the year for Kohl’s, the…