Review JSON-QB-API for missing functionality

[RickMoynihan]

We should review the OGI JSONQB api for any functionality we are missing.

See here for the currently supported API

[zeginis]

The functionality of the existing OGI JSON-QB API:

• get all cubes (supported by graphql-qb)
• support aggregations (ToDo)
• get cube meta-data (partially suported: title, description, ToDo: comment, issued, modified, license, publisher, subject)
• get cube dimensions (supported by graph-ql, ToDo: return both a URI and a label)
• get cube attributes i.e. qb.AttributeProperty (ToDo)
• get cube measures (ToDo see #19)
• get dimension values (supported by graphql-qb)
• get attribute values (ToDo)
• get dimension levels i.e. the hierarchical levels used at a dimension e.g. council area, electoral ward etc (ToDo)
• get slice (supported by graphql-qb)
• get table (Not supported. Are we going to use this or the slice is ok?)

[RickMoynihan]

get table (Not supported. Are we going to use this or the slice is ok?)

Yes I think we still want to produce lists of observations that correspond to these tables issue #17 is about this.