1. Re-enable DTD validation once
   https://github.com/UweSchmidt/hxt/issues/15 is fixed.

2. Write a test for test/xml/Odds_XML-long-import.xml once it no
   longer takes 10 minutes to import (Postgres only?).

3. Add support the the second type of weatherxml (see man page).

4. Add schema diagram for scores.

5. There are a few remaining document types that we need to parse
   before "version one point oh." This list refers to an
   old proprietary implementation, sorry:

     * AutoRaceResultsXML
     * jfilexml
     * Schedule_Changes_XML
     * scoresxml
     * GameInfoXML
     * SportInfoListing