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:

     * Schedule_Changes_XML

5. Update the list of schemagen files in htsn-import.cabal.

6. Test addition of a new field (weatherxml) and ensure that the
   database schema is updated accordingly. Document this fact in the
   man page.

7. We have DTDs but no sample XML for the following SportInfo types,
   which have therefore been left unimplmented for now:

   * Cbask_Indv_No_Avg_XML.dtd
   * Cbask_Indv_Shooting_XML.dtd
   * CBASK_StealsXML.dtd
   * Cbask_Team_Scoring_Rebound_Margin_XML.dtd
   * Cbask_Team_Scoring_XML.dtd
   * Cbask_Team_Shooting_Pct_XML.dtd
   * NFLGrassTurfDomeOutsideXML.dtd
   * NFLInterceptionLeadersXML.dtd
   * NFLPassingLeadersXML.dtd
   * NFLReceivingLeadersXML.dtd
   * NFLRushingLeadersXML.dtd
   * NFLTackleFFLeadersXML.dtd
   * NFLTopKickoffReturnXML.dtd
   * NFLTopPuntReturnXML.dtd
   * NFLYardsXML.dtd
   * NFL_PuntingLeaders_XML.dtd

8. The following DTD types were handled (in some form) by the old
   FeedGrabber. They are not yet handled by htsn-import (some may not
   be valid):

   * AutoRacingDriverList
   * AutoRacingGridXML
   * CBASK_Individual_Stats_XML
   * Cbask_Roster_XML
   * cbaskteamschedulexml
   * CBATeamScheduleXML
   * CFLTeamScheduleXML
   * CFLTotalTeamScheduleXML
   * earlylineXML
   * Minor_Baseball_TeamScheduleXML
   * MinorLeagueHockeyTeamScheduleXML
   * MLB_Boxscore_XML
   * MLB_earlylineXML
   * MLB_IndividualStats_XML
   * MLB_Probable_Pitchers_XML
   * MLB_Roster_XML
   * mlbteamschedulexml
   * mlsteamschedulexml
   * NBA_Boxscore_XML
   * NBA_Individual_Stats_XML
   * NBA_Roster_XML
   * nbateamschedulexml
   * NCAA_Basketball_Boxscore_XML
   * NCAA_FB_TeamScheduleXML
   * NCAAHockeyTeamScheduleXML
   * NFL_Boxscore_XML
   * NFL_CompBox_XML
   * nfldepthchartxml
   * nflteamschedulexml
   * nhlteamschedulexml
   * WCBaskTeamScheduleXML
   * WNBA_Boxscore_XML
   * WNBA_Individual_Stats_XML
   * WNBATeamScheduleXML