Spaniard Juanjo Mena returns to Heinz Hall to conduct a French program with the Pittsburgh Symphony.  Debussy’s “Pritemps” and Ravel’s “Noble and Sentimental Waltzes.”  Plus, Principal Flute Lorna McGhee with the Ibert Flute Concerto.  And you’ll hear Stravinsky’s “The Firebird,” written for Paris.