code: function( type, handler ) {
  
        var handlers = this._events[ type ]
        var position = handlers.indexOf( handler )
  
        if( handlers && ~position ) {
          if( handlers.length === 1 ) {
            this._events[ type ] = undefined
            delete this._events[ type ]
          } else {
            handlers.splice( position, 1 )
          }
        }
  
        return this
  
      }
docs: Remove a listener for the specified event
  @param  {String}   type
  @param  {Function} handler
  @return {Emitter}