CHESAPEAKE, Va, 2017-Jan-09 — /EPR Retail News/ — Dollar Tree, Inc. (NASDAQ: DLTR), North America's leading operator of discount variety stores, today (January 05, 2017) announced management changes, including the promotion of Gary Philbin and the addition of Duncan Mac Naughton. Gary Philbin, age 60, has been promoted to Enterprise President of Dollar Tree, Inc. In his…