Store RFC timestamp seed in mongodb
The source of truth in NOMAD are raw files. And everything that is not in a raw file, gets its truth from mongodb: comments, datasets, references (i.e. urls). Storing the RFC timestamps only in the archive does not fit this policy. Loading it from the old archive upon reprocessing is very ugly. Also these timestamps might become very important and should be handled with proper care.
We should store the RFC timestamp in mongodb, similar to comment
, references
, datasets
, entry_coauthors
. It does not necessarily need to be the full timestamp section with all properties, but some string that the actual timestamp model in the archive can be re-created from. The archive will still contain the timestamp and from there it is visible in the UI, but it will be read from mongo upon reprocessing and not from an old archive version.