feat: add local env setup documentation

[guilhem-barthes]

This PR addresses changes made after PR #193 has been merged

[guilhem-barthes]

@AlexandrePicosson In which category would you see it? My understanding was the section "Substra examples" and "Substrafl examples" were more deep dive into the use of the librairies. Should it be top-level?

[AlexandrePicosson]

Maybe we could add a category targeted more at developers @adarbier what is your opinion on this ?

[adarbier]

Yes I think it would be great to have a "Contributing to Substra" section with:

• High level guidelines for contributing
• How to locally run the substra stack (this doc basically)
• Maybe other sections? (build the doc, run the tests, submit a PR, etc.)

[guilhem-barthes]

For this PR I can create the category and move this page but I think the other points (including the front page of "Contributing to Substra") should be handled separately

[ThibaultFy]

Thanks a lot for the PR, the Sphinx features uses is perfect :D
@RomainGoussault do we want this page as the first one of the doc ? (which mean that when clicking on "next" from welcome page, we directly have this one)

[RomainGoussault]

Thanks a lot for the PR, the Sphinx features uses is perfect :D @RomainGoussault do we want this page as the first one of the doc ? (which mean that when clicking on "next" from welcome page, we directly have this one)

Thanks for the PR @guilhem-barthes. I feel this is weird to have this page at the top. I think once we have more things to put in a "Contributing Substra" section we could have one but for now I would keep the page in "Deploying Substra".

[RomainGoussault]

Other general comment, it is not clear to me how the "Deploying Substra" page relates to the "How-to" pages.
Should I start by the "Deploying Substra" page which will give a general overview and then move to the how to guides?

[RomainGoussault]

Thanks for the PR, that is much clearer now :)