lib/rtm-client.js
function(event, handler) {
    return events.on({
      listeners: this._listeners,
      event: event,
      handler: handler
    });
  }
function(event, handler) {
    return events.on({
      listeners: this._listeners,
      event: event,
      handler: handler
    });
  }
function ( event , handler ) { return events . on ( { listeners : this . _listeners , event : event , handler : handler } ) ; }
Register an event handler.

@param {String} event
@param {Function} handler
Register an event handler .