MB-7817: wait while all nodes will be updated

handle situation : couchApiBase doesn't exist in nodes/self

Change-Id: I16d9f809c3eb9739733cc7082e9f00fbff8125c3
Reviewed-on: http://review.couchbase.org/24853
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: Andrei Baranouski <andrei.baranouski@gmail.com>