We should add notes to metadata

[sthagen]

Notes are an important device to support incremantal and iterative workflows. They can be useful to identify the state of completion more clearly with details than a simple status field.

[LisaBobbitt]

This is a great addition.

[sthagen]

The current core schema already has the type defined in the JSON Schema at https://github.com/oasis-tcs/dps/blob/main/work-products/metadata-spec/json/data-provenance.json#L638

[sthagen]

What is left to do, is finding places in our schema, where we make use of this type.