Git submodules

[davide-f]

Closes #195

Changes proposed in this Pull Request

Revise pypsa-earth dependency with git submodules and revise atlite deprecation.

Major commands to reproduce this PR are: git submodule add {github url} : adds the package at {github url} as a submodule within the current folder. Optionally commits/branches/... can be specified Note that the version will fix the pypsa-earth version to the current commit.

To update the submodule version to the latest commit, the following command can be used followed by a commit&PR to the repo: git submodule update

With the new version, it is recommended to clone the repo using git clone --recurse-submodules update {repo path} to automatically clone the pypsa-earth-sec repo AND the pypsa-earth submodule. README has been updated accordingly.

If only git clone update {repo path} is used, hence without the --recurse-submodules, then the command git submodule init is needed to fill the repo.

I don't think this needs a release_note, but if not, I'll be happy to add it.

Checklist

• [x] I tested my contribution locally and it seems to work fine.
• [x] Code and workflow changes are sufficiently documented.
• [x] Newly introduced dependencies are added to envs/environment.yaml and envs/environment.docs.yaml.
• [x] Changes in configuration options are added in all of config.default.yaml, config.tutorial.yaml, and test/config.test1.yaml.
• [x] Changes in configuration options are also documented in doc/configtables/*.csv and line references are adjusted in doc/configuration.rst and doc/tutorial.rst.
• [ ] A note for the release notes doc/release_notes.rst is amended in the format of previous release notes, including reference to the requested PR.

[energyLS]

I have read into fixing the submodules to a certain commit. Not sure wether git reset --hard is the best way, I am not a git export though. I have asked ChatGPT, the answer seems to make sense. @davide-f what do you think?

P.S. I have checked it out and it works fine

[davide-f]

You mean: a. It is better to use checkout instead of reset: I agree b. To my knowledge and according to the guide, 'git submodule update' updates the entire workflow to the latest commit. I understand that it is possible to specify in the gitsubmodule the commit spec, but is it a good idea? That means that we keep by default a specific commit and it is very easy to loose track of what's going on in the main repo. That's why the proposal was to have that as an option

[energyLS]

You're right, we should keep it as it is. Just whenever needed we can set a specific commit, but not as default.