Adds a first implementation of the Answers API's prediction endpoint.
Design considerations
As the API is still in beta, this implem doesn't strongly type Answers parameters like query, queryLanguages, or returnExtractAttribute until these have a finalized status and naming.
I made the index a parameter, to allow for the same AnswersClient to target different indices successively - can be reconsidered if it makes it inconsistent with this client's users' expectations.
Describe your change
Adds a first implementation of the Answers API's
predictionendpoint.Design considerations
query,queryLanguages, orreturnExtractAttributeuntil these have a finalized status and naming.indexa parameter, to allow for the sameAnswersClientto target different indices successively - can be reconsidered if it makes it inconsistent with this client's users' expectations.