All due respect to Kevin Durant and the other ballers from Prince George’s County, recently celebrated in the Showtime documentary “In the Water,” but the District’s history of great basketball dates back to … well, damn near its creation, back to when Edwin B. Henderson introduced the game to the city, to the Washington 12 Streeters at the Colored YMCA more than a century ago, and to Howard University soon after. Henderson, a Naismith Memorial Basketball Hall of Fame inductee in 2013, learned the game at Harvard in 1904 from the inventor of the game, James Naismith.