By Walter Smelt
American punk was born in a dive bar and music club whose name stood for Country, Bluegrass and Blues, which is the kind of music the owner expected to book there. Instead, the Ramones started playing at CBGB's and turned the music world upside down. So in an upside-down kind of way, it seems appropriate that Somerville's own dive bar and music club should book bands whose members grew up on punk but found their way back to punk's roots in older American music: music like rockabilly, rhythm and blues, and country. Of course it's the Abbey Lounge we're talking about, which last Saturday night hosted a sold-out show in which all these traditions were represented-and not just represented, but resuscitated.