Bump version to 2.2.4

Author: Justin Greer

README.md

@@ -1,6 +1,17 @@
 Zencoder API PHP Library
 ==========================
 
+Company: [Brightcove/Zencoder](http://www.zencoder.com)
+
+Version: 2.2.4
+
+Date:    2019-09-05
+
+Repository: <http://github.com/zencoder/zencoder-php/>
+
+HTTP headers are handled in a case-insensitve manner so that they are compatible with HTTP2.
+
+
 Author:  [Nathan Sutton] (nsutton (a) brightcove (.) c&#1;om)
 
 Company: [Brightcove/Zencoder](http://www.zencoder.com)

Services/Zencoder.php

@@ -5,7 +5,7 @@
  * @category Services
  * @package  Services_Zencoder
  * @author   Michael Christopher <m@zencoder.com>
- * @version  Release: 2.2.3
+ * @version  Release: 2.2.4
  * @license  http://creativecommons.org/licenses/MIT/MIT
  * @link     http://github.com/zencoder/zencoder-php
  * @access   private
@@ -26,14 +26,14 @@ function Services_Zencoder_autoload($className)
  * @category Services
  * @package  Services_Zencoder
  * @author   Michael Christopher <m@zencoder.com>
- * @version  Release: 2.2.3
+ * @version  Release: 2.2.4
  * @license  http://creativecommons.org/licenses/MIT/MIT
  * @link     http://github.com/zencoder/zencoder-php
  */
 
 class Services_Zencoder extends Services_Zencoder_Base
 {
-    const USER_AGENT = 'ZencoderPHP v2.2.3';
+    const USER_AGENT = 'ZencoderPHP v2.2.4';
 
     /**
     * Contains the HTTP communication class