Skytrax has released the results of its annual World Airport Awards and, once again, Singapore's Changi Airport has taken the top spot. It's no surprise that Changi came out on top again. The international transit hub has incredible amenities, such as a butterfly garden, rooftop pool, movie theaters, hotels, spas, and showers — and even a four-story slide. Skytrax based its rankings on 12.85 million customer nominations across 110 nationalities and included 410 airports worldwide. It incorporated passenger satisfaction across nearly 40 categories, including service and shopping and security and immigration. All the airports commended last year made the 2014...