The venerable Rounder Records label, currently enjoying its 45th anniversary, has long been a leading light in the realm of roots music and Americana. But those terms need not be applied solely to one type of music. This month, as part of its ongoing digital catalogue initiative, Rounder is reissuing a number of titles blurring the genre lines of roots-rock and Americana. Some of the familiar names represented in this go-round include Ann Wilson of Heart, Laura Nyro, David