code: function constructAppUserModel(id, externalId, created, lastUpdated, scope, status, 
                              statusChanged, passwordChanged, syncState, lastSync, 
                              credentials, lastSync, links) {
      var model = {};
      if(id) model.id = id;
      if(externalId) model.externalId = externalId;
      if(created) model.created = created;
      if(lastUpdated) model.lastUpdated = lastUpdated;
      if(scope) model.scope = scope;
      if(status) model.status = status;
      if(statusChanged) model.statusChanged = statusChanged;
      if(passwordChanged) model.passwordChanged = passwordChanged;
      if(syncState) model.syncState = syncState;
      if(lastSync) model.lastSync = lastSync;
      if(credentials) model.credentials = credentials;
      if(lastSync) model.lastSync = lastSync;
      if(links) model.links = links;
  
      return model;
  }
docs: Constructs an object that reflects the structure of an App User Model
  @method constructAppUserModel
  @param id                unique key for User
  @param externalId        id of user in target app
  @param created           timestamp when app user was created
  @param lastUpdated       timestamp when app user was last updated
  @param scope             toggles the assignment between user or group scope
  @param status            status of app user
  @param statusChanged     timestamp when status was last changed
  @param passwordChanged   timestamp when app password last changed
  @param syncState         synchronization state for app user
  @param lastSync          timestamp when last sync operation was executed
  @param credentials       credentials for assigned app
  @param profile           app-specific profile for the user
  @param links             discoverable resources related to the app user
  @returns {}              the AppUserModel object