Add AuditLog Entry for Migration/Sync

[rootelement]

I'm thinking it might be too much to write what's changed like the API does. I think we can just put an entry in there for when a migration happens for a challenge uuid, and when a sync happens. Make sure it only writes an Audit if something is synced. If it looks up an ID and the ES versions match, it doesn't write anything to the DB, it shouldn't write an audit.