This PR cleans up the docs in a way to make them simpler to ingest by
our [docs repo](https://gitea.com/gitea/gitea-docusaurus).
1. It includes all of the sed invocations our ingestion did, removing
the need to do it at build time.
2. It replaces the shortcode variable replacement method with
`@variable@` style, simply for easier sed invocations when required.
3. It removes unused files and moves the docs up a level as cleanup.
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Signed-off-by: jolheiser <john.olheiser@gmail.com>
- **Installation**: includes how to install Gitea and related other
tools, also includes upgrade Gitea
- **Administration**: includes how to configure Gitea, customize Gitea
and manage Gitea instance out of Gitea admin UI
- **Usage**: includes how to use Gitea's functionalities. A sub
documentation is about packages, in future we could also include CI/CD
and others.
- **Development**: includes how to integrate with Gitea's API, how to
develop new features within Gitea
- **Contributing**: includes how to contribute code to Gitea
repositories.
After this is merged, I think we can have a sub-documentation of `Usage`
part named `Actions` to describe how to use Gitea actions
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Co-authored-by: John Olheiser <john.olheiser@gmail.com>
