Support for protocol-based sub-schemas

[cboettig]

When attempting to validate against a schema that uses sub-schemas referenced by a URL, we get an error:

 Don't yet support protocol-based sub schemas

Consider adding support for this? Is there a natural workaround meanwhile? (e.g. manually downloading the sub-schema first?)

[cboettig]

example of such a schema: https://github.com/radiantearth/stac-spec/tree/master/collection-spec/json-schema/collection.json

[richfitz]

Thanks @cboettig, I'm trying to remember why this was hard to implement and will come up with something. There is no workaround at present short of rewriting the schema unfortunately