Multi-thread game logic

[mtilden]

You're right that the whole of the server logic isn't threaded at this point but it IS something to look forward to and possibly with a configuration option so people can use all available threads or limit to how many they want (great for GSPs as well).

I myself haven't done much work with threading and with being thread-safe so I can't speak to the code of it much, but any such contributions would be appreciated by most, if not just me.

Cheers.