Vector class missing Hashlink implementation

Looks like Hashlink is missing its own implementation for the [Vector class](https://github.com/HaxeFoundation/haxe/blob/development/std/haxe/ds/Vector.hx). It seems to me that it should be possible with `hl.NativeArray`, but I wanted to raise an issue before making a PR with the needed changes - in case there was a reason this hasn't been done already.