MX-1223, change rollback algorithm to not require the entire pre-image of a document. Rollback now has multiple phases. First, we scroll back to accumulate the list of documents that need to be updated, then we get a snapshotted version of the affected documents, then we scan forward to the point where the snapshots where taken.
MX-1223, Change as many commands as possible to not go fatal if encountered
during the forward phase of rollback
MX-1223, add error codes