anchor.diff:  
   + Response 200 
   
  -
  -## Gamer VFS  [/gamer/vfs/{domain}/{key}]
  ++ Response 401
  +
  +        {
  +            "code" : "Unauthorized",
  +            "message" : "Invalid Gamer Credentials"
  +        }
  +        
  ++ Response 401 (application/json)
  +
  +        {
  +            "code" : "Unauthorized",
  +            "message" : "Invalid App Credentials"
  +        }
  +
  +## Gamer VFS  [/v1/gamer/vfs/{domain}/{key}]
   
   ### Get gamer's data [GET]
   
   ###### Possible values for error 404
   * `Key not found` ... the specified key doesn't exist
   * `Domain not found` ... the specified domain doesn't exist
  -
  -    Note: it should be 404 (resource not found), not 400 (bad request)
   
   ###### response description
   |Field|Description|Value|
  
positive.code: 
  It is your responsibility to store these to help the user log in later.
  
  Login for authenticated gamers will one of these : 
  
  * Facebook identity: use the `ID` and the `oauth token` from Facebook
  
  * Google+ identity: use the `ID` and the `oauth token` from Google+
  
  * RAW: use the `gamer_id` and the `gamer_secret` from a previous login
  
      Note: I've added RAW as a mean to login again, with gamer_id:secret
  
  ###### body description
  
  |Field|Description|Value|
  |---|---|---|
  |network|string, required|can be one of ["raw", "facebook", "googleplus"]
  |facebookid|string, required when {network=facebook}| the ID returned by facebook sdk
  |facebooktoken|string, required when {network=facebook}| the token returned by facebook sdk
  |googleplusid|string, required when {network=googleplus}| the ID returned by google sdk
  |googleplustoken|string, required when {network=googleplus}| the token returned by google sdk
  
      Note: maybe we should use `network, id, token` instead, to remove any ambiguity that login is using a single network...
  
  ###### response description
  |Field|Description|Value|
  |---|---|---|
  |gamer_id|string| user_id used in basic authentication for gamer authenticated requests
  
negative.code:             "message" : "Invalid App Credentials"
          }
  
  ## Logout [/v1/gamer/logout]
  
  Log a gamer out
  
  ### implementation
  * the gamer token has to be deleted on client-side!
  