For every car, there’s a prospective customer. And for a car like the Fiat 500C, a cutesy retro mini with a pseudo-cabrio sliding canvas roof, we hardly need to point out who that target demographic is. But as if to highlight what a difference the little things can make, the Abarthversion is another beast entirely.By “little things”, here we mean stuff like a 140-horsepower, 1.4-liter turbocharged four-cylinder engine, a five-speed sequential paddle-shift transmission and a badass two-tone paint job. All that may not sound like much, but when applied to a little thing like the 500C, it represents thedifference between the stock Fiat’s potential customer and the car nut who takes her out for an evening...