Add OAIS-related content to Archival extension

[nuest]

See https://github.com/o2r-project/erc-spec/blob/master/docs/spec/archival.md#oais---under-development

[ghost]

• [x] add information packages SIP, AIP, DIP
• [x] add representation information role and context of interpretability of ERC

[ghost]

included with 7bfb2afdd993c8fded48d8165ccb45f80cef6dc9