The spring cleaning is our responsibility. It’s a solid “thank you, ma’am” to Mother Nature (who, blizzards and spring snowfalls aside, is pretty darn good to us). Or if you prefer, consider it a down payment on the impending near-perfection that is a Maine summer. On Saturday, dog owners (and the people who love them) will spend the morning picking up what their four-legged sidekicks left behind. It’s April Stools Day, and cleanups are taking place at locations around Portland.