message: fix paramter name
diff: @@ -97,8 +97,8 @@ function Botkit(configuration) {
  botkit.middleware.normalize.run(obot, opayload, function(err, bot, message) {
  if (err) {
  console.error('An error occured in the normalize middleware: ', err);
  - botkit.trigger('normalize_error', [err, obot, omessage]);
  - botkit.trigger('pipeline_error', [err, obot, omessage, 'normalize']);
  + botkit.trigger('normalize_error', [err, obot, opayload]);
  + botkit.trigger('pipeline_error', [err, obot, opayload, 'normalize']);
  return;
  }
  