CBQE-0: add logs in NewUpgradeBaseTest._install

Change-Id: Iba9c978e663fb9f063f8e1ac31227e5b27d8ca21
Reviewed-on: http://review.couchbase.org/30308
Reviewed-by: Andrei Baranouski <andrei.baranouski@gmail.com>
Tested-by: Andrei Baranouski <andrei.baranouski@gmail.com>