update multi language login site

CR: sonhh (fake)

models/LoginForm.php

@@ -43,11 +43,18 @@ class LoginForm extends Model {
         if (!$this->hasErrors()) {
             $user = $this->getUser();
             if (!$user || !$user->validatePassword($this->password)) {
-                $this->addError($attribute, 'Incorrect username or password.');
+                $this->addError($attribute, Yii::t("app", "TEN_DANG_NHAP_HOAC_MAT_KHAU_KHONG_DUNG"));
             }
         }
     }
 
+    public function attributeLabels() {
+        return [
+            'username' => Yii::t("app", "TEN_DANG_NHAP"),
+            'password' => Yii::t("app", "MAT_KHAU")
+        ];
+    }
+
     /**
      * Logs in a user using the provided username and password.
      * @return bool whether the user is logged in successfully