Add support for Kotlin time API

[jcornaz]

Thanks to @alvaroReina we have support for java time API.

Turns out Kotlin recently started to ship an (experimental) multiplatform time API too. (Duration in the standard library and some other types in kotlinx-datetime)

We could start to support the Kotlin time API.

The experimental status of the kotlin time API should makes related generator experimental too, by marking such generators with the @ExperimentalTime annotation.

[jcornaz]

To avoid clashes between the Java and Kotlin APIs, we should probably have dedicated generator modules (generator-java-time and generator-kotlin-time for example).