ctdb/tests/integration: Update NFS tickles test and supporting code

ctdb/tests/integration: Update NFS tickles test and supporting code

This currently requires an eventscript to be dynamically installed.
This eventscript is only used to help determine when a monitor event
has occurred.  This code is horrible and fragile.

A better way is to just monitor the output of "ctdb scriptstatus".
When changes it changes then a monitor event has occurred.

Also remove the old code that checks for tickle information in shared
storage.  CTDB hasn't done things this way for a long time.

Signed-off-by: Martin Schwenke <martin@meltin.net>
Reviewed-by: Michael Adam <obnox@samba.org>