If you haven’t been to Monhegan Island, about 12 miles off the tip of Port Clyde in mid-coast Maine, go. Well, wait for summer, and then go. This is laid-back Maine at its best, a summer art colony with a terrific hotel overlooking the harbor and walking trails that don’t end. There are  no cars, and about 75 people live there year-round.  Picture an iconic Maine waterfront scene in your mind and you’ll find it on Monhegan. There is no marina (it’s not that kind of place). Instead, you hail the “harbormaster” when you arrive and he’ll come out in…