RALEIGH, N.C. (WNCN) - The CEO of a Raleigh marketing firm is apologizing for an ad posted on Twitter that depicted an ISIS execution - and a burger. Valor Media created the campaign for a Washington, D.C., chain called Z-Burger. Over the weekend, a tweet was sent out that showed a photo of American journalist James Foley moments before he was executed by ISIS in 2014 - along with the image of a hamburger. Z-Burger had the tweet removed within an hour. Michael Valor, whose business created the tweet, says he takes full responsibility and posted a video on Twitter...