Optionally remove the Status handler_id prefix

[lack]

What do these changes do?

As proposed in issue #319, this introduces an optional status_prefix boolean that can be added to any resource handler definition. If set to True (or omitted), status returned by the handler is still placed beneath the handler_id in the resulting object's status subresource. If set to False, the status returned by the handler is use at the top-level of the status subresource.

Description

Fully implements the proposal in issue #319.

Issues/PRs

Issues: #319

Type of changes

• New feature (non-breaking change which adds functionality)

Checklist

• [x] The code addresses only the mentioned problem, and this problem only
• [x] I think the code is well written
• [x] Unit tests for the changes exist
• [x] Documentation reflects the changes
• [x] If you provide code modification, please add yourself to CONTRIBUTORS.txt

[zincr[bot]]

🤖 zincr found 1 problem , 0 warnings

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Approvals

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[ps-jay]

This would be a really nice feature to have

[psontag]

Hey @lack, is there any chance you would be willing to update this branch and move the PR to the new repository at https://github.com/nolar/kopf?

If you don't have time at the moment would it be ok if I pick this up based on the changes you already made?

[lack]

@philipp-sontag-by : I'll try to redo this in the other repo, but I may not have time in the near future (starting a new job this week). I'd also be happy for you to carry this forward if you have time. Let me know here if you've got it in another PR so we don't duplicate effort.