Describe the solution you'd like
I would like to be be able to write such steps definitions:

Given("the following authors as entries") { (authors: Seq[Author]) =>
  // Some code
}

Rather than having to use Java types:

Given("the following authors as entries") { (authors: java.util.List[Author]) =>
  // Some code
}

Same goes for List[List[]] or List[Map[]].

Describe alternatives you've considered
Depending on the faisability, an alternative would be to provide in Cucumer Scala, some implicit methods to convert from DataTable to Scala types. And promote this usage in the documentation.

Additional note
This must not be a breaking change, if people rely on Java Types, their code should obvisouly still continue to work.