Implement legacy path pattern: IETF Internet-Drafts (`bibxml3`, `bibxml-id`)

[ronaldtse]

IETF Internet-Drafts (bibxml3, bibxml-id)

• (previous location) http://xml2rfc.tools.ietf.org/public/rfc/bibxml3/
• Pattern 1: http://xml2rfc.ietf.org/public/rfc/bibxml-ids/reference.I-D.example-name.xml
• Pattern 2: http://xml2rfc.ietf.org/public/rfc/bibxml-ids/reference.I-D.draft-example-name-99.xml

Legacy pattern(s) to implement:

• Pattern 1: https://{hostname}/public/rfc/bibxml-ids/reference.I-D.{example-name}.xml
• Pattern 2: https://{hostname}/public/rfc/bibxml-ids/reference.I-D.draft-{example-name}-{draft-number}.xml

We need to parse the pattern to return the appropriate BibXML content.