don't proceed if synchronization times out

If we allow any of the database setup steps to be skipped on any of the nodes, then when Pacemaker attempts to start up the resources, things will fail, and we'll experience fencing.  It's more user-friendly if
the chef-client run simply fails.

This may be a contentious change, or maybe I've just misunderstood something.  But based on my testing, the status quo doesn't look right, so we at least need to discuss this :)

In fact I'm wondering if `fatal` shouldn't default to `true` - that would be safer.