Wash the tomatoes and cut into thin slices. Cook the tomatoes, water, lemon juice and grated lemon in a medium saucepan, over medium heat, until the tomatoes are almost tender (about 10 minutes). Remove the tomatoes from the saucepan and set aside to cool. In a separate bowl combine the cornstarch, sugar and salt. When the tomato liquid has cooled, add the cornstarch mixture to the cooled liquid in the saucepan and cook over low heat until thickened. Add the tomatoes, cinnamon, and butter, and mix thoroughly. Pour the hot mixture into a pre-baked pie crust, add the top sheet of dough, pierce crust with fork to allow steam to escape and bake at 400 degrees for about 30-minutes, or until golden brown.