Courtesy We live in a Golden Age of water-repellency; before nylon shells and Gore-Tex membranes, humans devised hydrophobic clothing using vinyl, oiled canvas and, before that, cured seal and whale intestines. Now, (thankfully) waterproofing happens at a molecular level with advanced membranes that keep water droplets out but let body vapor (think sweat) through. The advancements have allowed rain jackets to become lighter, more breathable, packable and no less rain-proof. Rain jacket technology keeps getting better too — today, companies are experimenting with new fabrics to make rain shells softer and more comfortable and adding stretch for increased mobility (and less of that trademark crinkly jacket sound).Style hasn’t fallen by…