Add kotlin example

[pawelpasterz]

Simple kotlin example for Gradle export API

[guylabs]

Hi @pawelpasterz,

thanks a lot for this contribution! We appreciate the work you did and with this new sample based on Kotlin. We are currently restructuring these examples and will remove some that are now available. Due to this restructuring and the interoperability between Java and Kotlin we do not see the added value for another Kotlin example.

On top of this, the additional sample would increase our maintenance work for these samples on top of the other ones. One goal of this restructuring is to minimize the maintenance work even more.

Therefore we'll close this pull request and won't merge it. Feel free to keep this on your Github repository as an example.

Regards,
Guy