Login: No message is displayed when user tries to register with incorrect data

How to reproduce:
1. Go to JCommune

• Case1: Click "Sign In" in the header
• Case2: Open direct login link http://uat.jtalks.org/jcommune/login

2. Leave both fields empty
3. Click "Sign in"

AR:

• Case1: Fields are highlighted by red, but no text is displayed
• Case2: Only password field is highlighted with red, displayed message is quite unfriendly

ER:

• The same error message is displayed in both cases: page and dialog
• all fields with incorrect data are highlighted
• Error message provides more useful info to user
  E.g.
  ENG: "The username or password you entered is incorrect." (as gmail does)
  RU: "Неправильное имя пользователя или пароль"
  UKR: "Спроба увійти не вдалася, спробуйте ще раз"