Combine all-purpose and whole-wheat flours, cornmeal, brown sugar, baking powder, baking soda, cinnamon, ginger and salt in a mixing bowl; mix well, breaking up any lumps of brown sugar with your fingertips. Whisk together pumpkin, yogurt, oil, eggs and egg whites in another bowl until well combined. Stir the pumpkin mixture and cranberries (or raisins) into the dry ingredients until completely blended, but do not overmix. Divide the batter between the loaf pans, smoothing the tops with a spatula. Bake until a skewer inserted in the center comes out clean, 55 to 65 minutes. Let the loaves rest in the pans for 5 minutes; turn them out onto a wire rack to cool completely.