“Oh, What a Beautiful Mornin’, ” “My Funny Valentine,” “The Lady is a Tramp,” “The Sound of Music." With over 900 songs to his name, composer Richard Rodgers (1902-1979) left an indelible mark on American musical theater. His songs became an important part of the Great American Songbook, in part because jazz artists and singers loved to re-invent them. If Rodgers had had his way, though, he wouldn’t have let anyone else change a note. Why not?