Add support for symlinks

[AndreasBieber]

This PR adds support for symlinks (e.g. having git submodules in the repo):

.
└── repo
    ├── another-repo # git submodule
    │   └── docs
    │       └── index.md
    ├── docs
    │   ├── index.md
    │   └── sub-topic -> /repo/another-repo/docs/
    └── mkdocs.yaml

[timvink]

Thanks for your contribution! Nice work!

Elegant solution. I briefly thought there might be a performance hit by determining a repo for each file, but you solved that nicely by caching the directory of a file, so should be fine.

Just one question, is there any reason you choose to put this line in get_revision_date_for_file() instead of _get_repo() ?

https://github.com/timvink/mkdocs-git-revision-date-localized-plugin/blob/ee43666510e44e7d16746c272de81945f2fa7f26/mkdocs_git_revision_date_localized_plugin/util.py#L90

[AndreasBieber]

Yes, because the realpath is also needed when calling log. Otherwise git will complain that the path is outside of the repository.

[timvink]

Thanks @AndreasBieber 🎉

Will release a new version of this plugin tomorrow

[AndreasBieber]

Thx for the fast response and merge!