code: function AppServiceRegistration(appServiceUrl) {
      this.url = appServiceUrl;
      this.id = null;
      this.hs_token = null;
      this.as_token = null;
      this.sender_localpart = null;
      this.rate_limited = true;
      this.namespaces = {
          users: [],
          aliases: [],
          rooms: []
      };
      this.protocols = null;
      this._cachedRegex = {};
  }
docs: Construct a new application service registration.
  @constructor
  @param {string} appServiceUrl The base URL the AS can be reached via.