Spring’s almost here, which means it’s time for shirts with horizontal stripes, boat shoes, and other nautical-inspired clothes fit for Nantucket. This year, it’s all about knotted rope — whether on shoes, necklaces, or belts. If you want to fit in on the dock this year, you’d better tie one on. And if you don’t want to spend much dough accessorizing, just find a length of rope, tie a few artful bowllines, and voilà! you have a necklace.