Changes

Summary

1. Fix contents being deleted on upgrading a shulker box. Closes #26 (details)

Commit 00df219365a07c0a1634e96443cd8914f3c2b516 by alexbegt Fix contents being deleted on upgrading a shulker box. Closes #26
	src/main/java/com/progwml6/ironshulkerbox/common/items/ShulkerBoxUpgradeItem.java (diff)