Following the Engineering Proposal: More Efficient Replication for Container Writes, we should add support for the new batched ci/cu/cd oplog format, where we can support range insertions for int-keyed containers, batch insertions for string-keyed containers, and also multi-key arrays with an optional single value for all keys (and naturally no value on deletes).   This support would need to be added to container_oplog_entry.idl / oplog_entry.cpp, should support parsing, should be validated by unit tests.