Merge pull request #670 from watson-developer-cloud/backwards-compatibility

fix(NLU): Added backwards compatibility for version date constants

Author: germanattanasio

auth.js.enc

@@ -18,6 +18,9 @@ import extend = require('extend');
 import GeneratedNaturalLanguageUnderstandingV1 = require('./v1-generated');
 
 class NaturalLanguageUnderstandingV1 extends GeneratedNaturalLanguageUnderstandingV1 {
+  static VERSION_DATE_2016_01_23: string = '2016-01-23';
+  static VERSION_DATE_2017_02_27: string = '2017-02-27';
+
   constructor(options) {
     // For backward compatibility, allow version to be passed in version_date.
     const _options = extend({}, options);