This data will be used by tests in the following commit, which will
clone this branch to test git remotes.

This type implements `error` as a pointer.  If the type passed in is
not a pointer to a pointer, `errors.As()` panics.

Without this, FileNode things that `github.com/org/repo` is a file
location and it attempts to map it relative to itself.

Something tells me we should integrate both node types into some kind
of shared type, but for now this works.