Add more specific explodeLists overload that helps to avoid unnecessary cast

[koperagen]

Without this change, code would have to look like:

val df = dataFrameOf("list" to columnOf(listOf(1, 2, 3)))
            .gather { "list"<List<Int>>() }
            .explodeLists()
            .cast<Int>()
            .mapValues { listOf(it) }
            .into("key", "value")

Or even worse, without the cast it will be a Classcast exception in .mapValues { listOf(it) }
With this change, at least for simple case where all selected columns are List, cast won't be needed.