U.S.   –   A contrite George R.R. Martin has a message for fans, and “you won’t like it,” the author said in a blog post Saturday.The next novel in the series adapted by HBO as “Game of Thrones” is not finished. So HBO’s sixth season of the wildly popular show, slated to start in April, will almost certainly air before its source material is published.(CNN.COM/photo:cnn.com)…[+]