Fix Kotlin unit tests

[bleggett]

All 6 of the unit tests are currently disabled because they are failing.

We should fix them and re-enable them.

[ramnanib2]

The reason they are failing is because they assume DynamoDB credentials and table set up on the dev box where they're running from. Using DynamoDBLocal library should remove that hard dependency and allow us to add better tests:

https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/DynamoDBLocal.html

[mihn]

I can pick this up :)

[jmccance]

Looks like some work on this has been started here: #22