Fix NPE in ChestPage

Plugins/Mineplex.StaffServer/src/mineplex/staffServer/ui/chest/SupportChestPage.java

@@ -90,6 +90,9 @@ public class SupportChestPage extends SupportPage
 	private LinkedList<TreasureType> getTypesList()
 	{
 		return Arrays.stream(TreasureType.values())
+				// If there's no itemstack it's not a
+				// treasure chest
+				.filter(t -> t.getItemStack() != null)
 				.collect(Collectors.toCollection(LinkedList::new));
 	}