NASHVILLE, Tenn. — Andrew Jackson: President. Hero. Rock star. So reads a billboard welcoming arrivals at the Nashville International Airport, attempting to lure them from the honky-tonks of downtown Broadway to Jackson’s historic home called The Hermitage a few miles to the east. A new exhibit there encourages visitors to remember that the man with the lofty forehead and towering hair portrayed on the $20 bill had the star power of an Elvis Presley or Kanye West back in his day. It’s part of a …