Allow a roleOverride: Option[String] to be used when starting ClusterSharding for a given entry type. This will allow role defined clusters of ClusterSharding for entry types instead of requiring the role configuration to be all or nothing across all entry types.
- Move all entry related logic out of the ShardRegion and into a
new dedicated child `Shard` actor.
- Shard actor persists entry started and passivated messages.
- Non passivated entries get restarted on termination.
- Shard Coordinator restarts shards on other regions upon region failure or handoff
- Ensures shard rebalance restarts shards.
- Shard buffers messages after an EntryStarted is received until state persisted
- Shard buffers messages (still) after a Passivate is received until state persisted
- Shard will retry persisting state until success
- Shard will restart entries automatically (after a backoff) if not passivated and remembering entries
- Added Entry path change to the migration docs
* Add supervisor level that will start the ShardCoordinator again after
a configurable backoff duration
* Make the timeout of SharedLeveldbJournal configurable
* Include cause of PersistenceFailure in message of ActorKilledException
