GanttCalendarPlugin: use iso8601 format for `holiday.date` column


git-svn-id: http://svn.sourceforge.jp/svnroot/shibuya-trac/plugins/ganttcalendarplugin/trunk@848 456a77e7-5939-0410-b211-84f85430c667
GanttCalendarPlugin: refactored `admin.py` and use Trac db api since 0.12


git-svn-id: http://svn.sourceforge.jp/svnroot/shibuya-trac/plugins/ganttcalendarplugin/trunk@849 456a77e7-5939-0410-b211-84f85430c667
GanttCalendarPlugin: tweaked `setup.py` and make it executable


git-svn-id: http://svn.sourceforge.jp/svnroot/shibuya-trac/plugins/ganttcalendarplugin/trunk@850 456a77e7-5939-0410-b211-84f85430c667
GanttCalendarPlugin: bumped up the version to 0.6.3


git-svn-id: http://svn.sourceforge.jp/svnroot/shibuya-trac/plugins/ganttcalendarplugin/trunk@851 456a77e7-5939-0410-b211-84f85430c667