Cat proves size doesn't always matter in his neck of the woods. To his neighbors, he's a loner, a sometimes-friendly, sometimes- surly senior who spends his days wandering through the woods. He is particular about his yard. Strang ers are not always welcomed. But last week, Jack the cat be came a hero when he chased a black bear out of his neighbors' yard and up a tree. Twice. Last Sunday afternoon Suzanne Giovanetti was reading at the kitchen table when her husband Dean cried out from the TV room at the back of the house: A black bear had...