Config.yml Cleanup

[SaltyAimbOtter]

remove_items_after_respawn was only needed back in the day when Bukkit did not allow to check which Gamerules are set. Now Bukkit.getWorld("someWorld").getGameRuleValue() can be used to automatically set this config option.

This could be a part of #1037.

[SaltyAimbOtter]

Also change mysql config names (base -> database, pass -> password, user -> username)

[Wolf2323]

Maybe we rename the current condig to oldConfig.yml and add a new one that will replace piece for piece the config options