r18703: Fix the annoying effect that happens when nscd is running:

r18703: Fix the annoying effect that happens when nscd is running:

We usually do not get the results from user/group script modifications
immediately. A lot of users do add nscd restart/refresh commands into
their scripts to workaround that while we could flush the nscd caches
directly using libnscd.

Guenther
(This used to be commit 7db6ce295afbedfada7b207ad56566d2195a0d21)