docs: function Queue( subQueues ) {
    subQueues = subQueues || [];
    subQueues.push('default');
    subQueues = _.uniq(subQueues);
  
    this.queueNames = subQueues;
    this.__queues__ = {};
  
    subQueues.forEach(function( name ) {
      this.__queues__[name] = new SubQueue();
    }.bind(this));
  }