Support error response for authorization request

 * OAuth2 spec requires some error response on some situations
   Auhorization error:
    - Authorization Code grant type :
      http://tools.ietf.org/html/rfc6749#section-4.1.2.1
    - Implicit grant type:
      http://tools.ietf.org/html/rfc6749#section-4.2.2.1

   Token error:
    - Authorization Code, Resource Owner Password, Client Credential
      http://tools.ietf.org/html/rfc6749#section-5.2