Implement missing methods so that this compiles without errors

src/main/java/com/Acrobot/ChestShop/Containers/AdminInventory.java

@@ -67,6 +67,16 @@ public class AdminInventory implements Inventory {
     public void setContents(ItemStack[] itemStacks) {
     }
 
+    @Override
+    public ItemStack[] getStorageContents() {
+        return new ItemStack[0];
+    }
+
+    @Override
+    public void setStorageContents(ItemStack[] itemStacks) throws IllegalArgumentException {
+
+    }
+
     @Override
     public boolean contains(int i) {
         return true;