Add AIM Key authentication to Discovery Nodes

Author: chughts

README.md

@@ -8,10 +8,13 @@ Node-RED Watson Nodes for IBM Cloud
 <a href="https://cla-assistant.io/watson-developer-cloud/node-red-node-watson"><img src="https://cla-assistant.io/readme/badge/watson-developer-cloud/node-red-node-watson" alt="CLA assistant" /></a>
 
 ### New in version 0.6.15
-- Assistant, Speech to Text, Text to Speech, Tone Analyzer nodes updated to allow for use of iam key for authentication.
+- Assistant, Discovery, Speech to Text, Text to Speech, Tone Analyzer nodes updated
+to allow for use of iam key for authentication.
 - Migrated STT node off deprecated methods.
 - Fix to Tone Analyzer Node to preserve credentials on config reopen.
 - Fix to Tone Analyzer to allow json objects and arrays as payload.
+- Fix to STT where auto-connect was not being preserved when reopening configuration.
+- Bump to 2018-03-05 version date for Discovery service.
 
 ### New in version 0.6.14
 - Visual Recognition instances created post May 22 2018, have a new authentication mechanism