Fix Google authentication flow according to Google documentation

- Fixed IDE parsing errors (trailing commas)
- Fixed Google authentication flow according to Google documentation : https://developers.google.com/accounts/docs/OAuth2WebServer#handlingtheresponse

However, you may test your current implementation before include mine. For your information, my Google "project" has been created few hours ago.

The issue was, in my opinion, because Stormpath didn't follow the Google authentication for the server side but the client one. So a step was missing (convert oauth2 code into access token).