Nina Simone performs live on stage at the Newport Jazz Festival in Newport, R.I., on July 4, 1968. David Redfern/RedfernsMany music fans know that Nina Simone’s 1965 hit “I Put a Spell on You” helped establish the 32-year-old singer as the “High Priestess of Soul.” Few probably realize that it was Langston Hughes – the pioneering poet and face of the Harlem Renaissance – who had encouraged Simone to record it. As a Langston Hughes scholar, I’ve …