* DOC: improvements to developers documentation

* MNT: git rename a few files from the root directory

* DOC: more upgrades to development docs

* DEV: create script to delete local branches that no longer exist on remote

* DOC: I followed the step by step, looked at other parts of the documentation, and didn't find anything to correct or improve. I think it's fine as it is. I added a model to requirements.txt, which was missing when I ran the make html command.

* DOC: Update developer docs on sphinx building.

* DOC: Clarify testing structure on testing docs.

* DOC: Re-run docs requirements freeze.

* DOC: Introduce Conflicts Guideline and update First PR.

* DOC: fixing typos on development docs.

* DOC: Solve review comments of dev docs.

* DOC: final touches to developers documentation

* DOC: update cSpell configuration to enable additional file types

* DEV: move docker ignore file

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Co-authored-by: Julio Machado <julioromac@outlook.com>
Co-authored-by: Pedro Bressan <phmbressan@usp.br>
Co-authored-by: Lucas de Oliveira Prates <lucasdelprates@gmail.com>