MORE PERFECT UNIONAt age 93, Pete Seeger isn't actually retiring, just slowing down a bit. He's doing fewer concerts and his voice is a bit wobbly, but his heart is still open and his mind is still sharp. If you need proof, listen to the 16 songs on this album, 15 of them newly written by Seeger and his longtime friend and collaborator Lorre Wyatt. Wyatt's in his mid sixties, and a well known singer songwriter in his own right, but a severe stroke in 1996 left him