LU-198 Exit with error if NFSCLIENT is set, but no nfs export found

LU-198 Exit with error if NFSCLIENT is set, but no nfs export found

commit 2e7eb3a092fcc19a4550a677609f65f1fdd1e0d5
Date:   Thu Jan 27 14:58:48 2011 +0100

b=24410 exit with error if NFSCLIENT is set, but no nfs export found

a=Elena Gryaznova

Signed-off-by: YangSheng <ys@whamcloud.com>
Change-Id: I8d25737fa1ebd19729230bd38b423aa028527f3a
Reviewed-on: http://review.whamcloud.com/409
Reviewed-by: Brian J. Murrell <brian@whamcloud.com>
Tested-by: Hudson
Reviewed-by: Yu Jian <yujian@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>