The military usually isn’t the first organization that pops into your mind when someone says  “fall fashion.” Just take a quick look around the barracks at the boot Marines and junior soldiers rocking tucked-in polos with undershirts and sneakers for a night out at the local watering hole — not necessarily what you’d expect walking the streets of Madison Avenue. But the times they are a changin,’ and even the biggest brands want a piece of that warfighter style.