Has any stretch of real estate in D.C. turned itself around as quickly as Barracks Row? In just over six years the stretch of Eighth Street SE south of Eastern Market and north of M Street SE. has seen rapid development changing the area from one infested with drug traffic and petty crime to a vibrant thoroughfare. Sure, the space still has some bleak spots, including a Popeye’s with astonishingly bad service (even for a…