Yan 1330 obscore attributes

Added obscore attributes to the data product metadata.

I've added those attributes that were described in the most recent comments on ADR-55.

There are differences from the PST example:

Removed in this definition:

• dataproduct_subtype
• em_xel
• em_min
• em_max
• em_res_power
• em_resolution

Kept in this definition:

• obs_collection
• access_url
• access_format
• access_estsize

I've incorporated feedback from @awicenec on suitable default values.