WooCommerce, DIBS Payment Gateway - Add the DIBS Transaction ID to order emails

gistfile1.php

/**
 * Add the DIBS Transaction ID to order emails
 **/
add_filter('woocommerce_email_order_meta_keys', 'dibs_woocommerce_email_order_meta_keys');

function dibs_woocommerce_email_order_meta_keys( $keys ) {
	$keys['DIBS Transaction ID'] = 'dibs_transaction_no';
	return $keys;
}