Misc Cleanup

[XaserAcheron]

Lots of refactoring n' cleanup to do at some point, for sanity's sake:

• [x] Split all the base.txt files up into properly-named files (e.g. argWeapon.txt, argModWeapon.txt...).
• [x] Replace mod[] array with mod1/mod2 vars now that mods are classes.
• [ ] Remove ArgCounter from the project; that's some ugly bunk.
• [ ] Remove action keyword from non-Weapon/Inventory functions.
• [ ] Replace Arg_ function prefixes with something simpler, like X_. Easier to read that way.