AFK kick improvements, bans improvements, default user group and more JIT friendly hooks

- AFK time is reset when a player speaks in text or voice chat.
- Fixed the AFK kick plugin breaking if you disabled it then enabled it again on the same map.
- Added a default user group system so you can assign permissions/badges to everyone without a specific group.
- Bans plugin now syncs with the default NS2 bans file (thanks Ghoul).
- Improved bans plugin getting bans from the web, data is now cached like every other web-based system.
- Users can now be assigned using the Steam2 (STEAM_0:X:YYYY) and Steam3 ([U:1:YYYY]) formats.
- Fixed the binds file not being checked for valid JSON when looking for the vote button bind.
- Removed all frequent uses of pairs and replaced with a much faster iterator. Should avoid getting in LuaJIT's way.
- List headers now make a click sound when you click them.
- Made formatting much more consistent.