Enable caching of static files.

git-svn-id: https://simplesamlphp.googlecode.com/svn/trunk@2419 44740490-163a-0410-bde0-09ae8108e29a

www/module.php

@@ -164,6 +164,10 @@ try {
 
 	header('Content-Type: ' . $contentType);
 	header('Content-Length: ' . $contentLength);
+	header('Cache-Control: public,max-age=86400');
+	header('Expires: ' . gmdate('D, j M Y H:i:s \G\M\T', time() + 10*60));
+	header('Last-Modified: ' . gmdate('D, j M Y H:i:s \G\M\T', filemtime($path)));
+
 	readfile($path);
 	exit();