Normalized schema : light intensity and uv index

[colinsurprenant]

Related to #395

Summary

In /pull/524 the lightIntensity has been added under the air object.

Would it make more sense to have a separate light object which holds lightIntensity and where we could also add the uvIndex field also found in the SenseCAP S2120 per the discussion in https://www.thethingsnetwork.org/forum/t/sensecap-s2120-8-in-1-payload-edit/62487

Why do we need this?

• I am not sure I understand why light related metrics are under the air object?
• Also adding uvIndex would provide support for the SenseCAP 2120 UV and Light Intensity sensor.

Can you do this yourself and submit a Pull Request?

Yes.

I can submit a PR for the air object idea or just submit a PR for the addition of uvIndex under air depending on the outcome of the discussion here.

[KrishnaIyer]

@happyRip: this one as well.