Update to Google Oauth 2.0 login 

per the instructions at:
  https://developers.google.com/+/api/auth-migration#userinfo

This has not been extensively tested, but has been lightly tested in our application.

I believe this is done.  Please also review the change to JsonHelper!
OK. I don't remember attribute name using the dot, so I think the risk is pretty limited.

Thanks for taking time on this. Will merge.