COLUMBUS, Ohio — MLS scoring leader Kei Kamara had two goals, and the Columbus Crew snapped a six-game winless streak with a 2-1 comeback victory over the New England Revolution on Wednesday night. Columbus (5-6-5) avenged last season’s conference semifinal 7-3 aggregate loss to New England (6-6-6), which has lost four in a row on the road and nine of its last 10 games. Kamara scored the winner with his heal in the 50th minute for his 12th goal of the season. Lee Nguyen scored for the Revolution in the first 35 seconds, drilling in a shot from the top of the 18-yard box. The Crew answered right back in the fourth minute. Hector