Use persisted last_pp_seq_no for recovery of backup primaries

As of now, if master primary crashed (stopped) and re-started, it will get last_pp_seq_no from other Nodes and continue correct ordering.

For backup primaries this information is not propagated, so backup primary will start sending PRE-PREPARES from 1, and other nodes will reject it. It may eventually cause a memory leak, since ordering on this backup is stopped for some time.

Acceptance criteria

• Create a new key-value DB for persisting current states
• Persist last pp_seq_no for each Instance in the pool
• Use persisted last_pp_seq_no as a new pp_seq_no for a Replica if it's a primary in one of the Instances (including Master?)