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. 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
     * GameInfoXML
     * SportInfoListing

5. Try mass import of Auto_Racing_Schedule_XML.