Does the DocumentUri and CreationInformation need to be updated when upgrading document?

[goneall]

Currently, deprecated properties are "upgraded" to relationships when deserializing RDF documents. This is technically changing the model which should require a new, unique URI.

We may also want to update the creation information.

This issue came up in a discussion on the SPDX tech email list.

[goneall]

One possible solution is to add a couple optional parameters to the deserialize method:

• upgrade (default false)
• newDocumentUri (default null) New URI to use on upgrade

If upgrade is false and any deprecated properties are found, the deserialization will fail as unimplemented.