Split up civclicker-classes.js into separate files

[olleharstedt]

Make a folder called classes, put the classes in that folder, one class in each file named exactly the same as the class.

[Lukenickerson]

I'm not opposed to this. But there are some interdependencies that might need to be untangled, or at least make sure they are loaded in order.

[olleharstedt]

Done in my fork.