Bug fix, disciplines couldn't be deleted

The bug was in the strange behaviour of sql functions. The return value is presented in a table with strange column name. So I have just renamed it to `res`.

~dev_rating/application/classes/Controller/Api/Discipline.php

@@ -53,7 +53,7 @@ class Controller_Api_Discipline extends Controller_Api_Handler {
             throw new LogicException(Error::ILLEGAL_ACCESS);
         if ($discipline->isLocked)
             throw new LogicException(Error::DISCIPLINE_IS_LOCKED);
-        if (Model_Rating::countRatings($discipline) > 0)
+        if (Model_Rating::count($discipline) > 0)
             throw new LogicException(Error::DISCIPLINE_IS_LOCKED);
 
         $discipline->delete();

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

@@ -33,7 +33,7 @@ abstract class Controller_Api_Handler extends Controller_Handler {
         } catch (LogicException $e) {
             $answer = ['error' => [
                 'code'     => (int) $e->getCode(),
-                'message'  => 'One of the parameters specified was missing or invalid: ' . $e->getMessage(),
+                'message'  => (string) $e->getMessage(),
 //                'request'  => $this->request->params    // like http://vk.com/dev/captcha_error
             ]];
         }

~dev_rating/application/classes/Model/Rating.php

@@ -84,11 +84,12 @@ class Model_Rating extends Model
      * @param Model_Discipline $discipline
      * @return int
      */
-    public static function countRatings(Model_Discipline &$discipline) {
-        $sql = "SELECT `Discipline_CountRatings`(:id);";
+    public static function count(Model_Discipline &$discipline) {
+        $sql = "SELECT `Discipline_CountRatings`(:id) AS `res`;";
         $count = DB::query(Database::SELECT, $sql)
             ->param(':id', $discipline->ID)
-            ->execute()[0];
+            ->execute()
+            ->get('res');
 
         return (int) $count;
     }