libraries/password-manager: Don't fail when password-store dir contains wildcards.
libraries/password-manager: Don't fail when password-store dir contains wildcards.

`password-directory' is an OS path (a string), no need for `namestring'.

We must test if the directory exists, otherwise (format nil "~a/**/*.gpg" ...)
would expand to "NIL/**/*.gpg".

Finally, we replace the magic "4" by what it really stands for.

jmercouris/NeXT,jmercouris/NeXT