NEW YORK (Reuters) - Prominent black activist Al Sharpton has learned he is descended from a slave who was owned by ancestors of the one-time segregationist U.S. senator, the late Strom Thurmond, the Daily News reported on Sunday. The series of revelations came to light after the newspaper offered Sharpton a chance to delve into his family history with the help of genealogy experts from Ancestry.com. Sharpton learned of the connection this week, and told the News that "nothing -- nothing -- could prepare me for this." According to the genealogists' research, Sharpton's great-grandfather, Coleman Sharpton, was a slave in...