The Navy’s uniform history stretches back centuries, covering everything from Revolutionary War-era garb to iconic World War II khakis to modern-day aquaflage. And don’t forget those dinner-dress tiaras. But while some of these seabag selections may have earned cultural prominence, one milestone isn’t as well known. According to one manufacturer and several history books, the modern-day T-shirt will turn 100 this year, after being first issued to sailors in 1913. The T-shirt was introduced by the Navy as a way to get sailors to cover up the chest hair revealed by their V-neck uniforms, according to the book “Elsewhere, U.S.A:…