Add samples for Invoice Template API

sample/invoice-templates/DeleteInvoiceTemplate.php

@@ -0,0 +1,28 @@
+<?php
+
+// # Delete Invoice Template Sample
+// This sample code demonstrate how you can delete
+// an invoice template
+
+/** @var Template $template */
+$template = require 'CreateInvoiceTemplate.php';
+
+use PayPal\Api\Template;
+
+try {
+
+    // ### Delete Invoice Template
+    // Delete invoice object by calling the
+    // `delete` method
+    // on the Invoice Template class by passing a valid
+    // notification object
+    // (See bootstrap.php for more on `ApiContext`)
+    $deleteStatus = $template->delete($apiContext);
+} catch (Exception $ex) {
+    // NOTE: PLEASE DO NOT USE RESULTPRINTER CLASS IN YOUR ORIGINAL CODE. FOR SAMPLE ONLY
+    ResultPrinter::printError("Delete Invoice Template", "Template", null, $deleteStatus, $ex);
+    exit(1);
+}
+
+// NOTE: PLEASE DO NOT USE RESULTPRINTER CLASS IN YOUR ORIGINAL CODE. FOR SAMPLE ONLY
+ ResultPrinter::printResult("Delete Invoice Template", "Template", $template->getTemplateId(), null, null);