code: function Pubsub(bus, name) {
    events.EventEmitter.call(this);
    this.bus = bus;
    this.type = 'pubsub';
    this.id = "bus:pubsub:" + name;
    this.logger = bus.logger.withTag(this.id);
    this.name = name;
  }
docs: Pubsub. Do not instantiate directly, instead use {Bus#pubsub} to create a new Pubsub.
  @param bus
  @param name
  @constructor