In new albums, three innovative African musicians manage to turn what has been called neotraditionalism into a progressive style. Amadou & Miriam, Dimanche a Bamako (Nonesuch); Thione Seck, Orientation (Stern’s Africa); Daby Balde, Introducing Daby Balde (Introducing/World Music Network). By Milo Miles Starting in the late 1980s, the watchword for many leading African-pop performers was…