code review by hf: do remove from cart count to int

@@ -168,7 +168,7 @@ class CartModel
         $result = array('code' => 400, 'message' => '出错啦~');
 
         // 处理sku
-        $sku_list = json_encode(array($sku => $count));
+        $sku_list = json_encode(array($sku => intval($count) ));
 
         $remove = CartData::removeFromCart($uid, $sku_list, $shoppingKey);
         if ($remove && isset($remove['code'])) {