added interface annotations

Author: stefanak-michal

src/structures/IStructure.php

@@ -1,10 +1,15 @@
 <?php
 
-
 namespace Bolt\structures;
 
-
+/**
+ * interface IStructure
+ *
+ * @author Michal Stefanak
+ * @link https://github.com/neo4j-php/Bolt
+ * @package Bolt\structures
+ */
 interface IStructure
 {
     public function __toString () : string;
-}
+}