Generalized copy for optics

[serras]

This brings a small DSL which looks pretty much like Kotlin's built-in copy, but uses optics under the hood.

val p = Person("Alejandro", Address("Ergens", "Utrecht", "NL"))
val p2 = p.copy {
  Person.name transform { it.uppercase() }
  Person.address.street set "Nergens"
  inside(Person.address) {
    Address.city set "Madrid"
    Address.country set "ES"
  }
}

[nomisRev]

Small suggestion, and question.
Besides that it looks great @serras!! I think is an API many people have been looking for! 👏 👏

There have been many questions in the passed to update multiple fields using Optics.

[nomisRev]

Should we turn these into Knit examples?
Maybe we should discuss a documentation strategy for Arrow 2.0 in the weekly meeting? 🤔

[serras]

Yep, it would be nice to have Knit examples working instead of simple blocks.

[i-walker]

🤩 Wow that is really nice