Fix typo

This was revealed by PHPStan.

Feed.php

@@ -937,7 +937,7 @@ private function makeChannels()
             $out .= "</rdf:Seq>" . PHP_EOL . "</items>" . PHP_EOL . "</channel>" . PHP_EOL;
 
             // An image has its own element after the channel elements.
-            if (array_key_exists('image', $this->data))
+            if (array_key_exists('Image', $this->data))
                 $out .= $this->makeNode('image', $this->data['Image'], array('rdf:about' => $this->data['Image']['url']));
         } else if ($this->version == Feed::ATOM) {
             // ATOM feeds have a unique feed ID. Use the title channel element as key.

Item.php

@@ -32,28 +32,35 @@
  * @package         UniversalFeedWriter
  * @author          Anis uddin Ahmad <[email protected]>
  * @link            http://www.ajaxray.com/projects/rss
+ * @phpstan-type Element array{name: string, content: string, attributes: array<string, string>}
  */
 class Item
 {
     /**
     * Collection of feed item elements
+    *
+    * @var array<string, Element>
     */
     private $elements = array();
 
     /**
     * Contains the format of this feed.
+    *
+    * @var Feed::RSS1|Feed::RSS2|Feed::ATOM
     */
     private $version;
 
     /**
     * Is used as a suffix when multiple elements have the same name.
+    *
+    * @var int
     **/
     private $_cpt = 0;
 
     /**
     * Constructor
     *
-    * @param string $version constant (RSS1/RSS2/ATOM) RSS2 is default.
+    * @param Feed::RSS1|Feed::RSS2|Feed::ATOM $version constant (RSS1/RSS2/ATOM) RSS2 is default.
     */
     public function __construct($version = Feed::RSS2)
     {
@@ -77,7 +84,7 @@ private function cpt()
     * @access   public
     * @param    string $elementName    The tag name of an element
     * @param    string $content        The content of tag
-    * @param    array  $attributes     Attributes (if any) in 'attrName' => 'attrValue' format
+    * @param    array<string, string> $attributes Attributes (if any) in 'attrName' => 'attrValue' format
     * @param    boolean $overwrite     Specifies if an already existing element is overwritten.
     * @param    boolean $allowMultiple Specifies if multiple elements of the same name are allowed.
     * @return   self
@@ -113,7 +120,7 @@ public function addElement($elementName, $content, array $attributes = null, $ov
     * Elements which have attributes cannot be added by this method
     *
     * @access   public
-    * @param    array   array of elements in 'tagName' => 'tagContent' format.
+    * @param    array<string, string> array of elements in 'tagName' => 'tagContent' format.
     * @return   self
     */
     public function addElementArray(array $elementArray)
@@ -129,7 +136,7 @@ public function addElementArray(array $elementArray)
     * Return the collection of elements in this feed item
     *
     * @access   public
-    * @return   array   All elements of this item.
+    * @return   array<string, Element> All elements of this item.
     * @throws   InvalidOperationException on ATOM feeds if either a content or link element is missing.
     * @throws   InvalidOperationException on RSS1 feeds if a title or link element is missing.
     */