CBQE-2304 add cluster-wide collectinfo to pytest and conf dir

Change-Id: Ib57b5c63085a897d786dde7a473a8dc195044801
Reviewed-on: http://review.couchbase.org/39289
Tested-by: Thuan Nguyen <soccon@gmail.com>
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Thuan Nguyen <soccon@gmail.com>