anchor.diff:  An Identity can only map to a single User, so logging in as a particular
   identity unambiguously determines the User.
   
  -A User can have multiple Identities mapped to it. Multiple login methods can
  -identify the same User.
  +A User can have multiple Identities mapped to it. This allows multiple login
  +methods to identify the same User.
   
   Sample UserIdentityMapping:
   
  
positive.code: }
  ----
  
  <1> Identity name must be in the form providerName:providerUserName.
  <2> The name of the identity provider.
  <3> The name that uniquely represents this identity in the scope of the identity provider.
  <4> The name of the user this identity maps to.
  <5> The UID of the user this identity maps to.
  ====
  
  === User
  
negative.code: }
  
  ----
  <1> `name` is the token name, which is used as a bearer token to authenticate to
  the API.
  <2> The `clientName` value is the OAuthClient that requested this token.
  <3> The `expiresIn` value is the expiration in seconds from the
  creationTimestamp.
  <4> The `redirectURI` is where the user was redirected to during the
  authorization flow that resulted in this token.
  <5> `userName` represents the User this token allows authentication as.
  <6> `userUID` represents the User this token allows authentication as.
  <7> `authorizeToken` is the name of the OAuthAuthorizationToken used to obtain
  this token, if any.
  ====
  