Bill Clinton was at Symphony Hall on Thursday night to celebrate the 25th anniversary of the service organization City Year. While he was there, the former president picked up a City Year Legacy Award, which honored his dedication to the organization as well as his role in setting up City Year South Africa. The night also featured a performance by the Boston Pops and Judith Hill, a singer who was featured in the Oscar-winning documentary “Twenty Feet From Stardom.”Mark Shanahan can be reached at email@example.com. Follow him on Twitter @MarkAShanahan. Meredith Goldstein can be reached at firstname.lastname@example.org. Follow her on Twitter @MeredithGoldste.