anchor.diff:  
   === Authenticate Me
   
  -Let's jump right in with an example of authentication.
  +Let's jump right in with an example of authentication. For the Google oAuth authentication to work you should follow these steps:
  +
  +1. Read on [Google Developers Help](https://developers.google.com/identity/protocols/OAuth2) how to obtain OAuth 2.0 credentials such as a client ID and client secret that are known to both Google and your application.
  +2. Set `Authorized redirect URIs` to `http://localhost:3000/auth/page/googleemail2/complete`.
  +3. Enable `Google+ API` and `Contacts API`.
  +4. Once you have the `clientId` and `secretId`, replace them in the code below.
   
   [source, haskell]
   ----
  
positive.code: import           Yesod
  import           Yesod.Auth
  import           Yesod.Auth.BrowserId
  import           Yesod.Auth.GoogleEmail
  
  data App = App
      { httpManager :: Manager
  
negative.code: 
      authPlugins _ =
          [ authBrowserId def
          , authGoogleEmail clientId clientSecret
          ]
  
      authHttpManager = httpManager
  