Alarm support in HBase Part 1

Two additional tables are introduced for alarms and alarm_history.
Ordering in alarm_history was achived by that fact that HBase
stores entries in alphabetical order. It is needed to enlarge the
preciseness of reverse_timestamp because alarms history entries may be
generated once per second, especially in tests.

Partially implements bp hbase-alarming

Change-Id: I41bc60f13779899af0e8f8e01f85b2ee6d1c8aae
Merge "Alarm support in HBase Part 1"