Renaming Namespaces and Organizing Classes

- Updated OpenId classes to be in API namespace
- Updated PP Naming Convention to PayPal Naming Convention
- FormatConverter Class got its own namespace
- Handlers are grouped in Handler namespace
- Samples and Tests Updated Accordingly

lib/PayPal/Transport/PayPalRestCall.php

@@ -0,0 +1,79 @@
+<?php
+namespace PayPal\Transport;
+
+use PayPal\Core\PayPalLoggingManager;
+use PayPal\Core\PayPalHttpConfig;
+use PayPal\Core\PayPalHttpConnection;
+use PayPal\Rest\ApiContext;
+
+/**
+ * Class PayPalRestCall
+ *
+ * @package PayPal\Transport
+ */
+class PayPalRestCall
+{
+
+
+    /**
+     * Paypal Logger
+     *
+     * @var PayPalLoggingManager logger interface
+     */
+    private $logger;
+
+    /**
+     * API Context
+     *
+     * @var ApiContext
+     */
+    private $apiContext;
+
+
+    /**
+     * Default Constructor
+     *
+     * @param ApiContext $apiContext
+     */
+    public function __construct(ApiContext $apiContext)
+    {
+        $this->apiContext = $apiContext;
+        $this->logger = PayPalLoggingManager::getInstance(__CLASS__);
+    }
+
+    /**
+     * @param array  $handlers Array of handlers
+     * @param string $path     Resource path relative to base service endpoint
+     * @param string $method   HTTP method - one of GET, POST, PUT, DELETE, PATCH etc
+     * @param string $data     Request payload
+     * @param array  $headers  HTTP headers
+     * @return mixed
+     * @throws \PayPal\Exception\PayPalConnectionException
+     */
+    public function execute($handlers = array(), $path, $method, $data = '', $headers = array())
+    {
+
+        $config = $this->apiContext->getConfig();
+        $httpConfig = new PayPalHttpConfig(null, $method);
+        $headers = $headers ? $headers : array();
+        $httpConfig->setHeaders($headers +
+            array(
+                'Content-Type' => 'application/json'
+            )
+        );
+
+        /** @var \Paypal\Handler\IPayPalHandler $handler */
+        foreach ($handlers as $handler) {
+            if (!is_object($handler)) {
+                $fullHandler = "\\" . (string)$handler;
+                $handler = new $fullHandler($this->apiContext);
+            }
+            $handler->handle($httpConfig, $data, array('path' => $path, 'apiContext' => $this->apiContext));
+        }
+        $connection = new PayPalHttpConnection($httpConfig, $config);
+        $response = $connection->execute($data);
+
+        return $response;
+    }
+
+}