v2.3.0

• Add ISO 8601 “week year” (%G and %g). Thanks, @davinov! #52
• Fix shortDays in locale zh-TW. Thanks, @muyueh! #84
• Fix time format in locale ja-JP. Thanks, @mandel59! #77
• Fix datetime format in locale nl-NL. Thanks, @mdbel! #88
• Fix datetime format in locale fr-FR. #85