getStringForItemStack

/**
 * Borrowed this from forestry
 * @param itemStack
 * @return
 */
    @Nullable
    public static String getStringForItemStack(ItemStack itemStack) {
        if (itemStack.isEmpty()) {
            return null;
        }

        Item item = itemStack.getItem();
        String itemStackString = getItemNameFromRegistryAsString(item);
        if (itemStackString == null) {
            return null;
        }

        int meta = itemStack.getItemDamage();
        if (meta != OreDictionary.WILDCARD_VALUE) {
            return itemStackString + ':' + meta;
        } else {
            return itemStackString;
        }
    }
    /**
     * @return The registry name of the item as {@link String}
     */
    @Nullable
    public static String getItemNameFromRegistryAsString(Item item) {
        ResourceLocation rl = item.getRegistryName();
        return rl == null ? null : rl.toString();
    }