Move PotionEffects out of Game.java so they only get loaded once

Signed-off-by: Andre Schweiger <andre.spiele@yahoo.de>
Change GameMode on Gamestart

Signed-off-by: Andre Schweiger <andre.spiele@yahoo.de>
Fix Itemstand save/load bug

Signed-off-by: Andre Schweiger <andre.spiele@yahoo.de>