Add equals(ItemStack) to IAEItemStack contract.

src/api/java/appeng/api/storage/data/IAEItemStack.java

@@ -106,4 +106,13 @@ public interface IAEItemStack extends IAEStack<IAEItemStack> {
      * @return definition stack
      */
     ItemStack getDefinition();
+
+    /**
+     * Compare this AE item stack to another item stack, but ignores
+     * the amount. It checks the item type, NBT and damage values.
+     *
+     * @param is An item stack
+     */
+    boolean equals(ItemStack is);
+
 }