Add Vanilla Co-operative to Organisational Types

[ColmMassey]

Some data sets will indicate that an organisation is a co-op, but not what type of co-op. Do we use the ESSGlobal legal-form which has a vanilla Cooperative label, or add a generic _Co_operative_it to our newly minted Organisation Strusture.

[joebillings]

I think we'll need to add a generic one as I don't think we can switch between SKOSs like that

[ColmMassey]

Lets do that.

[joebillings]

Here is the vanilla coop: http://vocabs.solidarityeconomy.coop/essglobal/V2a/html-content/essglobal.html#organisational-structure-OS115