minor #1158 Fix return of renderView to string (bburnichon)

This PR was merged into the 1.2 branch.

Discussion
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Fix return of renderView to string

Commits
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988753a4 Fix return of renderView to string

src/Silex/Application/TwigTrait.php

@@ -56,7 +56,7 @@ trait TwigTrait
      * @param string $view       The view name
      * @param array  $parameters An array of parameters to pass to the view
      *
-     * @return Response A Response instance
+     * @return string The rendered view
      */
     public function renderView($view, array $parameters = array())
     {