NASHVILLE, Tennessee (Reuters) – Aaron Lewis stands as one of the more unusual crossovers into country music, but the singer of the metal band Staind believes it was a fit made in the cradle. "It's been quite the pleasant eclectic mix of tattoos and black eyeliner, and Stetsons, cowboy boots and big shiny buckles," Lewis said in an interview after the release of his first full-length country studio album, "The Road," this week. Lewis, 40, was raised on what he terms his grandfather's country music: Johnny Cash, Waylon Jennings, Charlie Daniels and George Jones. …