WorldSpaceFlight code changes

The WorldSpaceFlight pages dealing with the various flights (US, Russia, China) have undergone a behind-the-scenes update. A new class was introduced which eliminates a lot of code duplication and makes maintenance easier. Of course, this means a number of modules had to be changed to accommodate the new class structure. I might have missed something. If you notice anything “funky” about a particular page, please let me know so I can fix it. This can be something like weird characters, misplaced text, missing data, inappropriate data like a number where text is expected, or some kind of error message.