• Add test with Time::Zone (GH#25) (Michal Josef Špaček)
  
• Add test with bad Time::Zone string (GH#26) (Michal Josef Špaček)
  
• Add tests with negative time (GH#26) (Michal Josef Špaček)
  
• Replace all instances of \d with [0-9] in regular expressions to
  reject non-ASCII Unicode digits, with a regression test (GH#27)
  (Robert Rothenberg)
  
• Reject malformed ISO 8601 timezones with a doubled colon (GH#31)
  (Olaf Alders)
  
• Document day/month/year ordering for numeric dates (GH#32) (Olaf
  Alders)