GitLab

to python3

See merge request !1

Not sure it's a bug but still it seems that the Draft4Validator
expects the "id" being replaced with "$id" althoug it should be only
true with Draft6Validator according to this:
https://json-schema.org/draft-06/json-schema-release-notes.html#q-what-are-the-changes-between-draft-04-and-draft-06

It remove a lot of flexibility provided by the JSON format...
In a next version of the format, we could specify a "sanctioned way" to
create non-standard properties, like prefixing their names with an underscore.

GeometryCollection doesn't make any sense for now, since MultiPolygon is
already a collection of polygons