Eventscripts: work around NFS restart failure under load.

Eventscripts: work around NFS restart failure under load.

"service nfs restart" can fail.  To stop nfsd it sends a SIGINT and
nfsd might take a while to process it if the system is loaded.
Starting nfsd may then fail because resources are still in use.

This does some /proc magic to tell nfsd to do no more processing.  It
then runs service stop, kills nfsd with SIGKILL, and then runs service
start.  This is much less likely to fail.

Signed-off-by: Martin Schwenke <martin@meltin.net>