Add ability to decode json in different ways and combine the results

[pjoneswork]

This is a different zip functionality. Instead of combining decoders with inside a tuple, this allows us to decode the same json twice.

Given the setup:

final case class Foo(a: Int)
final case class Bar(b: String)

implicit val fooDecoder: JsonDecoder[Foo] = DeriveJsonDecoder.gen[Foo]
implicit val barDecoder: JsonDecoder[Bar] = DeriveJsonDecoder.gen[Bar]

The old zip does

implicit val fooAndBarDecoder: JsonDecoder[(Foo, Bar)] = JsonDecoder[Foo].zip(JsonDecoder[Bar])
val json = """[{"a": 1}, {"b": "2"}]"""
val result: (Foo, Bar) = json.fromJson[(Foo, Bar)]

while newZip does

implicit val fooAndBarDecoder: JsonDecoder[(Foo, Bar)] = JsonDecoder[Foo].newZip(JsonDecoder[Bar])

val json = """{"a": 1, "b": "2"}"""
val result: (Foo, Bar) = json.fromJson[(Foo, Bar)]

Fixes #487

[987Nabil]

I think this is a good feature. But the naming is nod good ;). I think the right name is and.
@fsvehla maybe you have an opinion too?

[guizmaii]

I agree the name is meh. and is a good suggestion :)