/**
* The FollowerInitialSyncUpStatus is sent by a Follower to inform any RaftActor subclass whether the Follower
* is at least at the same commitIndex as the Leader was when it sent the follower the very first heartbeat.
*
* This status can be used to determine if a Follower has caught up with the current Leader in an upgrade scenario
* for example.
/**
* The FollowerInitialSyncUpStatus is sent by a Follower to inform any RaftActor subclass whether the Follower
* is at least at the same commitIndex as the Leader was when it sent the follower the very first heartbeat.
*
* This status can be used to determine if a Follower has caught up with the current Leader in an upgrade scenario
* for example.