Feature: Add support for nav repos

[jdoiro3]

New feature details in #11

This PR adds the support for nav_repos. See example below.

plugins:
  - search
  - multirepo:
      # (optional) tells multirepo to cleanup the temporary directory after site is built.
      cleanup: false
      nav_repos:
        - name: backstage
          import_url: https://github.com/backstage/backstage
          # forward slash is needed in '/README.md' so that only the README.md in the root
          # directory is imported and not all README.md files.
          imports: [
            docs/publishing.md, docs/integrations/index.md, /README.md,
            # asset files needed
            docs/assets/*
            ]
        - name: fast-api
          import_url: https://github.com/tiangolo/fastapi
          imports: [docs/en/docs/index.md]

nav:
  - Backstage:
      - Home: backstage/README.md
      - Integration: backstage/docs/integrations/index.md
      - Publishing: backstage/docs/publishing.md
  - FastAPI: fast-api/docs/en/docs/index.md
  # you can still use the !import statement
  - MkdocStrings: '!import https://github.com/mkdocstrings/mkdocstrings'

In addition to the new nav_repos config, this PR adds support for a !import statement to include keep_docs_dir. If set to true the docs directory will not be removed from the directory tree.

TODO

• update docs
• write tests
• see if I can consolidate/simplify configuration for users.

[github-actions]

Version Number Check

Version has been updated in pyproject.toml.