CLUSTER also needs a Null_flavour

Description

If a Element can be null, seems reasonable to allow that to a Cluster for the exact same reasons (e.g. there could be reasons to not being able to get a series of measurements and then an empty Cluster with a reason would be created)
We can also discuss if it should go to ITEM or ITEM_STRUCTURE (or leave it until we redo the ITEM_STRUCTURE classes)
I remember hearing that CIMI has also gone this way, but probably Thomas knows better.

Environment

None

Reporter

Diego Bosca

Labels

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Components

Affects versions

Priority

Minor
Configure