Adds ability to store attributes in their own columns

[sklarsa]

First of all, thanks for this project! As someone who works for QuestDB and also just bought a house, this has been a lifesaver for me in starting my homeassistant journey!

Since our ILP protocol creates columns when it encounters unknowns, I figured that it might be useful to split out the attributes column into multiple columns for easier querying purposes. I left the default behavior the same, just added the split_attributes config option.

This is running successfully on my homeassistant, but I'm happy to keep this running for a little bit to ensure its stability.

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EDIT: Ah, and I already hit an issue with a list value :-( Maybe unstructured storage is the way to go here for now

[CM000n]

Hi @sklarsa, never mind 😉 Thank you very much for your contribution and your ideas. Feel free to share if you have any more of them!