Dust off and clean up MySQL support

[jdolan]

The game module has MySQL spaghetti code throughout it. Let's try to consolidate it, and make sure that it works and is documented correctly. We should also make sure we provide a valid schema / ddl to seed the database.

[wickedshell]

Is there an old schema sitting somewhere that I can use as a starting point, or should I be figuring it out purely from the code?

[maci]

IIRC, the schema back then was not quite optimal either. I think it makes more sense to design a proper schema without redundancy etc and then change the code.

[jdolan]

The base schema was ..eh; what was missing was some temporary cron-rebuilt tables for providing fast aggregate views (heh, if only proper *views* didn't perform so poorly in MySQL). Also, I'm not crazy about the fact that I didn't use numeric pk's for the player table. That should probably be rethought.

The old schema and PHP scripts are kicking around in stats/trunk. Note that I wrote all of that like 10 years ago for Quetoo; it is likely very, very bad.