[csw-maintainers] Let's delete the 'current' symlink

[Maciej (Matchek) Bliziński]

We maintained it for backward compatibility. But I think in practice
it confuses people, they think there's a release (or a branch) called
'current', or that whatever is in there, is up to date. All of that is
not so, and maybe our users are better of without the symlink? I
propose that we delete it, or replace it with a stub like we did with
the 'stable' branch.

Maciej