CBQE-927: offline_cluster_upgrade with/out indexing before upgrade

Change-Id: I88b04ecaa3047cf3f5b3a5e6a0b7a53fe38979b6
Reviewed-on: http://review.couchbase.org/24826
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>