include.php

См. документацию.

<?php
 
\Bitrix\Main\Loader::registerAutoLoadClasses('b24connector', array(
    '\Bitrix\B24Connector\Helper'       =>  'lib/helper.php',
    '\Bitrix\B24Connector\Button'       =>  'lib/button.php',
    '\Bitrix\B24Connector\Connection'   =>  'lib/connection.php',
    '\Bitrix\B24Connector\ButtonTable'  =>  'lib/buttontable.php'
));