The best friend of Oscar Grant who was there the night a BART police officer fatally shot the unarmed man was shot and killed at a Hayward gas station, authorities and friends said today. Johntue Caldwell, 25, of Fremont was found behind the wheel of a car parked at the 76 gas station at West Tennyson Road and Calaroga Avenue at about 5:35 p.m. Friday, according to police and friends. The victim had been sitting in the car when at someone walked up to the vehicle and fired several rounds, said Hayward police Lt. Roger Keener. The assailant fled and...