feat(Subscription): support azure service bus destination

Closes #331

src/Core/Model/Subscription/AzureServiceBusDestination.php

@@ -0,0 +1,41 @@
+<?php
+/**
+ * @author @jayS-de <jens.schulze@commercetools.de>
+ */
+
+namespace Commercetools\Core\Model\Subscription;
+
+use Commercetools\Core\Model\Common\Context;
+
+/**
+ * @package Commercetools\Core\Model\Subscription
+ *
+ * @method string getType()
+ * @method AzureServiceBusDestination setType(string $type = null)
+ * @method string getConnectionString()
+ * @method AzureServiceBusDestination setConnectionString(string $connectionString = null)
+ */
+class AzureServiceBusDestination extends Destination
+{
+    public function fieldDefinitions()
+    {
+        return [
+            'type' => [static::TYPE => 'string'],
+            'connectionString' => [static::TYPE => 'string'],
+        ];
+    }
+
+    /**
+     * @param $connectionString
+     * @param $accessKey
+     * @param $accessSecret
+     * @param Context|null $context
+     * @return AzureServiceBusDestination
+     */
+    public static function ofQueueURLAccessKeyAndSecret($connectionString, Context $context = null)
+    {
+        return static::of($context)
+            ->setType('AzureServiceBus')
+            ->setConnectionString($connectionString);
+    }
+}