Add support for Watson service endpoints

[jeancarl]

Only the default Dallas location for the Watson service endpoint is currently supported by the nodes. Add support for other Watson service endpoints listed below via a companion select box for each API key input.

Watson Assistant (https://cloud.ibm.com/apidocs/assistant#service-endpoint):

• Dallas: https://gateway.watsonplatform.net/assistant/api
• Washington, DC: https://gateway-wdc.watsonplatform.net/assistant/api
• Frankfurt: https://gateway-fra.watsonplatform.net/assistant/api
• Sydney: https://gateway-syd.watsonplatform.net/assistant/api
• Tokyo: https://gateway-tok.watsonplatform.net/assistant/api
• London: https://gateway-lon.watsonplatform.net/assistant/api

Language Translator (https://cloud.ibm.com/apidocs/language-translator#service-endpoint):

• Dallas: https://gateway.watsonplatform.net/language-translator/api
• Washington DC: https://gateway-wdc.watsonplatform.net/language-translator/api
• Frankfurt: https://gateway-fra.watsonplatform.net/language-translator/api
• Sydney: https://gateway-syd.watsonplatform.net/language-translator/api
• Tokyo: https://gateway-tok.watsonplatform.net/language-translator/api
• London: https://gateway-lon.watsonplatform.net/language-translator/api

Speech to Text (https://cloud.ibm.com/apidocs/speech-to-text#service-endpoint):

• Dallas: https://stream.watsonplatform.net/speech-to-text/api
• Washington, DC: https://gateway-wdc.watsonplatform.net/speech-to-text/api
• Frankfurt: https://stream-fra.watsonplatform.net/speech-to-text/api
• Sydney: https://gateway-syd.watsonplatform.net/speech-to-text/api
• Tokyo: https://gateway-tok.watsonplatform.net/speech-to-text/api
• London: https://gateway-lon.watsonplatform.net/speech-to-text/api

Text to Speech (https://cloud.ibm.com/apidocs/text-to-speech#service-endpoint)

• Dallas: https://stream.watsonplatform.net/text-to-speech/api
• Washington DC: https://gateway-wdc.watsonplatform.net/text-to-speech/api
• Frankfurt: https://stream-fra.watsonplatform.net/text-to-speech/api
• Sydney: https://gateway-syd.watsonplatform.net/text-to-speech/api
• Tokyo: https://gateway-tok.watsonplatform.net/text-to-speech/api
• London: https://gateway-lon.watsonplatform.net/text-to-speech/api

Tone Analyzer (https://cloud.ibm.com/apidocs/tone-analyzer#service-endpoint):

• Dallas: https://gateway.watsonplatform.net/tone-analyzer/api
• Washington DC: https://gateway-wdc.watsonplatform.net/tone-analyzer/api
• Frankfurt: https://gateway-fra.watsonplatform.net/tone-analyzer/api
• Sydney: https://gateway-syd.watsonplatform.net/tone-analyzer/api
• Tokyo: https://gateway-tok.watsonplatform.net/tone-analyzer/api
• London: https://gateway-lon.watsonplatform.net/tone-analyzer/api

[chunyianliew]

IBM Changed has the end point again for newly created AI services: https://cloud.ibm.com/apidocs/assistant/assistant-v2

In the example given in the above page you can see that the URL of the endpoint is now including a instance reference: https://api.us-south.assistant.watson.cloud.ibm.com/instances/6bbda3b3-d572-45e1-8c54-22d6ed9e52c2

Next to that, two additional locations have become available for the Visual Recognition Service next to Dallas: Frankfurt and Seoul. See https://cloud.ibm.com/apidocs/visual-recognition/visual-recognition-v4 for more information.

Wouldn't it be easier to just allow the configuration of the End Point URL's as a simple open text fields instead of pre-configured picklist listing the available locations?