“On the subject of spinach,” screenwriter Delia Ephron, younger sister of Nora, advises, “divide into little piles. Rearrange again into new piles. After five or six maneuvers, sit back and say you are full.” This directive, from Ephron’s book “How to Eat Like a Child,” reinforces the long-held stereotype that kids, and not a few adults, hate spinach. They know better in Chester, Illinois, just fifty miles from where I sit. That’s because Chester is the home town of Elzie Crisler Segar, the