nullable-collaborator

record nullable-collaborator {
  avatar-url: string,
  email: option​<string>,
  events-url: string,
  followers-url: string,
  following-url: string,
  gists-url: string,
  gravatar-id: string,
  html-url: string,
  id: s32,
  login: string,
  name: option​<string>,
  node-id: string,
  organizations-url: string,
  permissions: option​<nullable-collaborator-permissions>,
  received-events-url: string,
  repos-url: string,
  role-name: string,
  site-admin: bool,
  starred-url: string,
  subscriptions-url: string,
  type-op: string,
  url: string,
}