Panic at serde_json's Value serialization

[Niedzwiedzw]

https://github.com/Niedzwiedzw/serde-xml-rs/blob/bfd38c52440cca274819b6f84f12d47ceb438fa3/tests/test.rs#L173 right so this is a showcase of a panic, @RReverser, is this behavior intentional?

[punkstarman]

@Niedzwiedzw, the serializer is quite simply lacking support for a lot of cases.

With the lockdown, I don't have much time to devote to much besides family and my day job.

I will see what I can do soon.

[Niedzwiedzw]

I've opened up a PR for my solution, I guess its good enough