Possibility to send additional data to payload

[alecat88]

I want to be able to send complex objects (array, objects, class) in the payload.
The achievement would be to have multiple key=value entries in the logs as it is already for the existing "timestamp, kind, message, level, sdk_name, ...

At the moment all I can send is just a string. If I send an object it gets converted to a string "[Object object]" making it unhelpful.

At the same time, if I use the context, every label gets added a "_context" prefix, which is not what I want.

My last goal is then, to have log lines with extra labels:
eg: timestamp="..." kind=... message="..." level=.. extraField=.... anotherExtraField={"array": [1,2,3]}