BEIJING (Reuters) -Recovery crews on Sunday found the second black box – the flight data recorder – from the wreckage of a China Eastern Airlines Boeing 737-800 jet that crashed into a mountainside in southern China. Flight MU5735 crashed on Monday, killing all 132 people onboard, mainland China’s deadliest aviation disaster in 28 years. Heading to coastal Guangzhou from the southwestern city of Kunming, the plane dived from cruising altitude around the time it should have started its landing descent. The dead included nine crew members. The black box, which could shed light on the cause of th…