Andres

> @nrxus seems like there is a CI issue @LucioFranco Hm weird, it doesn't seem to be related to this PR at all. It looks like the latest rust is...

@LucioFranco another ping since I think it's all ready (:

@LucioFranco I've rebased to latest master that fixed the clippy issue. I believe it's ready to merge but it needs you to hit approve again.

@djc do you mind reviewing this?

I think this is useful even outside of Futures. My application doesn't do any async but whenever we create a new thread we also create a new tracing span for...

What's the reason behind putting these methods in `TransactionData` instead of directly in `Transaction`, `Span`, and `TransactionOrSpan`? This way it looks like `TransactionData`'s intent was as an iterator of transaction...

I apologize about the multiple force pushes yesterday, I was chewing on it yesterday a bit more since it wasn't reviewed yet and decided to move some stuff around to...

I have finished the work to also support flattening when serializing with `flavor = "enforced_order"`. It's on a separate branch though since I wasn't sure if this PR was already...

@wprzytula would you mind taking a look at this PR and tell me if you would like me to keep it as-is or add the flatten support to the `enforced_order`...

@Lorak-mmk , could you take a look and let me know if there are any concerns holding this PR?