Don't export named graph?

[lecoqlibre]

This is to remind that we should not be exporting the name of the graph (@id) in JSON-LD. Indeed, some parsing libraries could refuse to parse named graph like related here: https://github.com/datafoodconsortium/connector-php/issues/1.

Unfortunately, it seems there is no option to tell VocBench to not export the name of the selected graph. So we probably have to ensure this manually.

Or maybe we should rely on parsing libraries that can support named graphs?

Acceptance Criteria

As this is valid JSON-LD, and we cannot (easily) modify the VOCbench output. We have decided the following:

• [ ] We will require users of the standard to use parsing libraries that support named graphs
• [ ] We will document this in the standard
• [ ] We will provide a list of parsing libraries we know support this
• [ ] We will provide sample code that can strip the @id from files, when required.