Local host-id may not be set when replaying commit log

The local host id is now used when replaying commit logs to prevent data loss when moving SSTables between nodes (CASSANDRA-16619).

The local host-id is assigned once on initial startup and persisted to the local.local table for use on subsequent startups - however it remains in the memtable/commitlog until the local table is eventually flushed.

If the node dies for any reason before the flush takes place, on the next restart a new host id will be allocated before the commit log is replayed and any sstables appearing in the commit log will be skipped incorrectly.