Merge pull request #20 from Guite/master

add missing return type hint

src/DependencyInjection/Configuration.php

@@ -7,7 +7,7 @@
 
 class Configuration implements ConfigurationInterface
 {
-    public function getConfigTreeBuilder()
+    public function getConfigTreeBuilder(): TreeBuilder
     {
         $tb = new TreeBuilder('goetas_multipart_upload');