[Kotlin] Codegen API doc from C headers

[hewigovens]

Dokka https://github.com/Kotlin/dokka

[optout21]

Most non-test swift code is generated, so codegen logic has to be extended to:

• read descriptions from source files (TW*.h)
• generate documentation comments in a common format, understood by documenting tool

[hewigovens]

@Milerius can you update your finding here?

[Milerius]

@Milerius can you update your finding here?

Kotlin comments use Asterix style: https://kotlinlang.org/docs/kotlin-doc.html

We need to find a good way with a script similar to the swift one to convert the /// doxygen comments into Kotlin one. I suggest to use sed or perl with regex once again

[Milerius]

Implemented in #2678