Removed two debug messages when the player is registered within Minetweak
Moved registerPlayer and unregisterPlayer to the Player class, from Minetweak.class.
Changed Minetweak to Player inside of ServerConfigurationManager.
Removed demo references, and demo entirely. Demo classes still being ridded of.
Removed demo classes, and references to demo locales.
Changed PlayerChatEvent to use a instance of the player, not a username String.
More lowercase username improvements.
Removed startup message about Minetweak version, and Minecraft version. Will implement another one, which will use Minecraft's logger.
Merge remote-tracking branch 'origin/1.6.2' into 1.6.2