WARWICK — What strikes fellow police officers most about Police Chief Stephen McCartney is his humility.After nearly 20 years as the city's chief, McCartney, who is 71, is retiring. His last day on the job is next Friday. "I think it's time," he said. "There's not much more for me to do."Colleagues say McCartney was old-school — a fair, honest and thoughtful leader who never sought the limelight. "He has been one of the best mentors I've [...]