The Great White Way and graphic design have had a long, storied love affair, from the simple lines of a Hirschfeld caricature to the show-selling broadsheets, cab toppers and streetlamp pennants that seem to grab the man on the street by his sharp lapels and plunk him in an orchestra seat for a 7:30 curtain. This rundown of the posters of the 2015 season features many throwbacks keeping the tradition a…