EST-301: add status to suspend lease, also track lease status changes in a separate entity LeaseStatusReason

* Only bulk invoice calculations ignore suspended leases, manual override on the lease is possible.
EST-280: enable remove for new invoices on selected invoice summary; copy new lease from existing one
EST-298: the index availability is later then initially configured
EST-280: Move numerators to administration menu; add some tests for global setting
EST-304: always update the base value from the previous term
EST-301: add timestamp on clock service, needed when adding new lease status reasons
ST-301: fix api integration test