#279 Add new method to set span status.

[maeserichar]

Just an easy change to avoid needing to import status in order to set the status of a span.

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[victoraugustolls]

This was partially discussed here!

@reyang What do you think?

[lzchen]

With this change, is there a need for the Status class?
What do you think @victoraugustolls @reyang ?

EDIT: Just saw the previous thread, this seems fine. Also, just realized removing Status would be a breaking change.

[victoraugustolls]

This seems to me more like a helper method, and I wouldn't remove Status class, as not only it is a breaking change but is referenced in OT spec as mandatory, and it would make the job a lot difficult in the migration in case it was removed.

In my opinion, I would rather have utils method and not add it inside the Span class, but it is a personal view, would wait @reyang for comments.

[reyang]

I agree with @victoraugustolls.

[maeserichar]

Great! So something in the line of setSpanStatus(span, code, message, details) in `trace/utils.py' would be more aligned with that?