Cubesummary nobt

[pp-mo]

🚀 Pull Request

Description

New code for first eyes. Replaces #3962

Replaced beautifultable with minimalist home-brew solution for printing text entries in columns.

Still WIP

TODO : better code comments + proper testing
FUTURE : This should convert into a follow-on to #3952, when that is done. It will need resolving against changes in that.
IN PROGRESS : I'm working on replacing actual cube summaries with this, and fixing existing tests for that.

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Consult Iris pull request check list

[bjlittle]

@pp-mo Is this PR active? I'm guessing not since it's targeting v3.0.x...

Can it be closed?

[pp-mo]

@bjlittle Is this PR active? ... Can it be closed?

This is just a heads-up + draft to show thinking.
It was against v3.0.x as we started there in anticipation of the merge back to master.

I have new code, re-targetted against master, but I am waiting for #3988 before making a PR, as we are still making changes there to the underlying implementation of the CubeSummary class, so requiring re-basing of the CubePrintout code.
When #3988 is done, I will close this and replace it.

We agreed yesterday that we will put this CubePrintout code onto master, but keep it private (or maybe in iris.experimental).
Meanwhile, the switch to finally replace the existing Cube.summary() implementation with this will be done initially on the "mesh-data-model" feature branch instead -- just so that we can defer the additional work to fix any awkward test knockons, like its breaking Cube._repr_html_().

[pp-mo]

Replaced by #3998