Create a website for the RDF IRI's in the spec

[goneall]

In SPDX 2.X, if you went to the URL represented by the IRI for a class or property, you went to an actual HTML page describing the spec. For SPDX 3.0, we would need separate HTML files for the spec.

If these files are generated, we can upload those to the AWS S3 bucket and publish them.

[goneall]

One possible solution is to just generate redirects to the MKDocs github.io pages.

Attached is an example HTML page which redirects to the Core page.

The example is what is currently used to redirect from http://spdx.org/rdf/ontology/spdx-3-0-1
index.html.txt