upgrade Date cardtype+issues

Want to be able to start with them blank.

Have sorting work (would if months always a zero, but they come out with and without).

Be able to add a time.

Express beginning/ending date/time

Recurring dates (Google Calendar is a good peer here)

Sometimes you're not sure yet when something is happening. Express fuzzy dates (maybe a Pointer of dates?)

Integrate with or better yet just implement our own group date-finding tools.

(Also see Implement microformats - so that we can use http://microformats.org/wiki/hcalendar hcalendar.)