new kotlin tutorials

[nathanfallet]

Linked to rabbitmq/rabbitmq-website#2322

[michaelklishin]

@nathanfallet thank you for your ongoing contributions!

[michaelklishin]

Just to clarify a couple of things:

1. Moving an existing Kotlin tutorial that uses the Java client is perfectly fine
2. Committing things like generated Gradle or Maven wrappers into this repo is also fine

However, I'm afraid these days we have to ask you @nathanfallet to sign our contributor CLA. It's under two pages long and uses a legally binding digital signing service.

[nathanfallet]

@michaelklishin I'm doing this right now (for the CLA; I just sent the email request).

For the points you mentioned:

1. Yeah we already validate that before
2. The gradle wrapper is expected to be part of the repo, it's the base that downloads the appropriate Gradle distribution for the user (on their local machine in their home .gradle folder) so that they can build the project. Every gradle project has it included in the git.

Also, PR is ready, I'll edit the message when CLA is signed.

[michaelklishin]

@nathanfallet sorry, I cannot find your request. Can you please resend?

[nathanfallet]

You're right, just verified it was the wrong email (a ".dot." was left at the wrong place). Just resent!

EDIT: It's signed!