THEATER: With his zany imagination and distinctive bass-baritone voice, Joseph Keckler (myspace) has been generating buzz throughout the gooey honeycomb of the downtown performance art cabaret scene. Tonight he sprinkles his particular blend of whimsical catnip at Dixon Place with Cat Lady, in which a man re-enacts an ordinary day with his mother, who runs a community theater with cat actors out of her home. “Past lives are recalled, songs are sung, and finally a......