{ Error: Not Authorized
    at Request._callback (/Volumes/hd2/Projekte/vi-com-bot-service/node_modules/watson-developer-cloud/lib/requestwrapper.js:87:15)
    at Request.self.callback (/Volumes/hd2/Projekte/vi-com-bot-service/node_modules/watson-developer-cloud/node_modules/request/request.js:188:22)
    at emitTwo (events.js:106:13)
    at Request.emit (events.js:191:7)
    at Request.<anonymous> (/Volumes/hd2/Projekte/vi-com-bot-service/node_modules/watson-developer-cloud/node_modules/request/request.js:1171:10)
    at emitOne (events.js:96:13)
    at Request.emit (events.js:188:7)
    at IncomingMessage.<anonymous> (/Volumes/hd2/Projekte/vi-com-bot-service/node_modules/watson-developer-cloud/node_modules/request/request.js:1091:12)
    at IncomingMessage.g (events.js:291:16)
    at emitNone (events.js:91:20)
  code: 401,
  error: 'Not Authorized',
  description: '2017-06-01T08:57:57-04:00, Error ERCDPLTFRM-DNLKUPERR occurred when accessing https://gateway.watsonplatform.net/conversation/api/v1/workspaces/dc8097e8-fea7-47a3-80ed-57c43321377e/message?version=2017-04-21, Tran-Id: gateway-dp01-2475007148 - Invalid UserId and/or Password. Please confirm that your credentials match the end-point you are trying to access. A common error is trying to use credentials from an experimental or beta release against a GA release or vice versa' }

url: 'https://gateway-fra.watsonplatform.net/conversation/api/'

var conversation = new ConversationV1({
  username: '<username>',
  password: '<password>',
  version_date: ConversationV1.VERSION_DATE_2017_05_26
});