Added missing methods in ListBlockInterface

Author: Martin Brecht-Precht

src/Block/ListBlockInterface.php

@@ -23,4 +23,16 @@ public function getListBlockType();
 	 */
 	public function getListItems();
 
+	/**
+	 * @param ListItemInterface $listItem
+	 * @return $this
+	 */
+	public function addListItem(ListItemInterface $listItem);
+
+	/**
+	 * @param ListItemInterface[] $listItems
+	 * @return $this
+	 */
+	public function addListItems(array $listItems);
+
 }