code: function addScopedHandler (event, handler, scope) {
      if (handlers[event] === undefined) {
          handlers[event] = [];
      }
  
      let scopedHandler = scope ? handler.bind(scope) : handler;
  
      handlers[event].push({
          original: handler,
          scoped: scopedHandler
      });
  
      return scopedHandler;
  }
docs: [getScopedHandler description]
  @method addScopedHandler
  @param  {String}   event    [description]
  @param  {Function} handler [description]
  @param  {Object}   scope    [description]
  @return {Function} The scoped handler