title: pin payment error - vendor/autoload.php not found
body: <p>I have installed composer on my pc and running a pin payment script.</p>
  
  <pre><code>require_once __DIR__.'/vendor/autoload.php';
  use Omnipay\Common\GatewayFactory;
  $gateway = GatewayFactory::create('Pin');
  $gateway-&gt;setSecretKey('1111111111');
  $gateway-&gt;purchase(array(
      'email'       =&gt; 'abc.php2@gmail.com',
      'description' =&gt; 'Widgets',
      'amount'      =&gt; '49.99',
      'currency'    =&gt; 'USD',
      'card_token'  =&gt; $_REQUEST['card_token'],
      'ip_address'  =&gt; $_REQUEST['ip_address']
  ))-&gt;send();
  </code></pre>
  
  <p>I am not sure about <strong>require_once _<em>DIR</em>_.'/vendor/autoload.php';</strong> , where can i find the exact path for the same.</p>