Enabled Vault Credit Card List API

- Added Credit Card List API Operation
- Updated Credit Card to include new properties
- Updated Tests
- Updated Samples
- Fixed Billing Agreement Sample (Expired Set Date).

sample/vault/CreateCreditCard.php

@@ -22,6 +22,17 @@ $card->setType("visa")
     ->setFirstName("Joe")
     ->setLastName("Shopper");
 
+// ### Additional Information
+// Now you can also store the information that could help you connect
+// your users with the stored credit cards.
+// All these three fields could be used for storing any information that could help merchant to point the card.
+// However, Ideally, MerchantId could be used to categorize stores, apps, websites, etc.
+// ExternalCardId could be used for uniquely identifying the card per MerchantId. So, combination of "MerchantId" and "ExternalCardId" should be unique.
+// ExternalCustomerId could be userId, user email, etc to group multiple cards per user.
+$card->setMerchantId("MyStore1");
+$card->setExternalCardId("CardNumber123" . uniqid());
+$card->setExternalCustomerId("123123-myUser1@something.com");
+
 // For Sample Purposes Only.
 $request = clone $card;
 

sample/vault/ListCreditCards.php

@@ -0,0 +1,36 @@
+<?php
+
+// # List Credit Card Sample
+// The CreditCard resource allows you to
+// retrieve all previously saved CreditCards.
+// API called: '/v1/vault/credit-cards'
+// Documentation: https://developer.paypal.com/webapps/developer/docs/api/#list-credit-card-resources
+
+// Creating a Credit Card just in case
+/** @var CreditCard $card */
+$card = require 'CreateCreditCard.php';
+
+use PayPal\Api\CreditCard;
+
+/// ### List All Credit Cards
+// (See bootstrap.php for more on `ApiContext`)
+try {
+    // ### Parameters to Filter
+    // There are many possible filters that you could apply to it. For complete list, please refere to developer docs at above link.
+
+    $params = array(
+        "sort_by" => "create_time",
+        "sort_order" => "desc",
+        "merchant_id" => "MyStore1"  // Filtering by MerchantId set during CreateCreditCard.
+    );
+    $cards = CreditCard::all($params, $apiContext);
+} catch (Exception $ex) {
+    // NOTE: PLEASE DO NOT USE RESULTPRINTER CLASS IN YOUR ORIGINAL CODE. FOR SAMPLE ONLY
+ 	ResultPrinter::printError("List All Credit Cards", "CreditCardList", null, $params, $ex);
+    exit(1);
+}
+
+// NOTE: PLEASE DO NOT USE RESULTPRINTER CLASS IN YOUR ORIGINAL CODE. FOR SAMPLE ONLY
+ ResultPrinter::printResult("List All Credit Cards", "CreditCardList", null, $params, $cards);
+
+return $card;