It's the bane of alley cats, de rigueur decoration for newlyweds' cars, and the primary device behind many children's first telephone. But, according to The Wiley Encyclopedia of Packaging Technology, it's also the greatest influence ever on the food habits of the civilized world. It's the tin can. For those of us used to modern conveniences, it's hard to imagine what life was like before the invention of the tin can. In the winter months, for example, people had no access to seasonal fruits and