json-schema-org
Update output to make the root object an overview with results contained inside
This makes progress toward some of what is discussed in https://github.com/json-schema-org/json-schema-spec/issues/1065.
Basically, we need a place to include metadata about an evaluation. This PR wraps the existing output in a root node that can contains any such metadata.
(As a side effect, it creates a purpose for the root object in the case of the "list" format, which could have just been an array before.)
Re-reading through the issue, it seems that dialect should be part of the output unit itself rather than the summary. Still... I think the summary root node is a good addition.
I'll remove dialect from this PR and do another one for that then.
I know we had a discussion somewhere on having some more "global" details in the root node, though...