More patches as part of #1225. Change the 'core' modules to use the json::reply

method to set the content type header and encode the response as a json object

modules/exif/controllers/exif.php

@@ -28,6 +28,6 @@ class Exif_Controller extends Controller {
     $view = new View("exif_dialog.html");
     $view->details = exif::get($item);
 
-    print json_encode(array("form" => (string) $view));
+    json::reply(array("form" => (string) $view));
   }
 }