Former mayor Ed Koch has published a new children’s book, “Eddie Shapes Up,” described by its publisher, Zagat (yes, they of the little red book), as “the story of a boy who with the support of his friends and family decides to change his lifestyle in order to make his life happier and healthier.” Earlier today he read from the book to a group of children at P.S. 64 Robert Simon on East Sixth Street, with Department of Transportation Commissioner Janette Sadik-Khan on hand to help launch the D.O.T.’s Walk Ways program, an initiative to encourage and facilitate walking to school. The Local was there to see how the former mayor was doin’.