rcdn only removes symlinks

Picture this case:

    % ls -l ~/.a
    ~/.a -> ~/.dotfiles/a
    % tree ~/.dotfiles/a
    a
    `-- b
        `-- c
            `-- d
                `-- foo

Ideally we would want `~/.a/b/c/d/foo` to be the symlink, and the rest
to be actual directories. However, some people did it differently.

Running `rcdn` on the above would previously have removed `foo` from
`~/.dotfiles`. Now, it removes `~/.a` and nothing more.