A man in Cook County is eating the jail.The mentally ill man removes screws from furniture, pieces of metal and even strips of leather from his restraints and attempts to eat them.Because of that, he is kept in a room by himself, often naked, and is watched around the clock by a correctional officer.He has cost taxpayers close to $1 million in health bills.Cook County Sheriff Thomas J. Dart told that story Thursday at a City Club of Chicago luncheon.It is, Dart said, an example of the strain on correctional facilities …