 Bob Dylan has called Johnny one of America's greatest songwriters of all time. A lot of folks have. And guess what? His new record is called Songwriter. Of course, he didn't choose that title. He's been gone for more than 20 years. But there is a new posthumous album out of almost entirely unheard songs by Johnny Cash that were originally recorded back in 1993, never released. The musician who made all of this possible is...