From the first sparkling notes of his intro to Luiz Bonfá’s “Manha De Carnaval”, originally recorded for the soundtrack to the classic film, Orfeu Negro (“Black Orpheus”), it was clear that Kenny Barron is a master pianist who plays with soul, grace, wit, and technique. His first set on Saturday at the Kennedy Center’s Family Theater saw him play 90 minutes of polished jazz that was pleasing to the ear, but there was something missing….