Merge branch 'issue312_error_messages' into develop

~dev_rating/application/classes/Controller/Handler/Rating.php

@@ -29,10 +29,16 @@ class Controller_Handler_Rating extends Controller_Handler
             $_POST['submoduleID'],
             $_POST['rate']
         );
-        if (!is_null($error))
-            throw HTTP_Exception::factory($error['code'], $error['message']);
-
-        $this->response->body(json_encode([ 'success' => true ]));
+        if (!is_null($error)) {
+            if (!is_null($error['message'])) {
+                $this->response->body(json_encode(['success' => false, 'message' => $error['message']]));
+                $this->response->status(400);
+            } else {
+                throw HTTP_Exception::factory($error['code'], $error['message']);
+            }
+        } else {
+            $this->response->body(json_encode(['success' => true]));
+        }
     }
 
     public function action_SetExamPeriodOption() {