MB-11051: Add module tests for failover table

Change-Id: I21e9dc006ff0156b2c92c309ac61d0a7f3035f6b
Reviewed-on: http://review.couchbase.org/37873
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>