Here base plugins for making lists of for datebook.
this moment planned:
- plugin displaying birthdays from contacts
- base christian holidays (christmas, ash wednesday, easter,
  palm sunday, Ascension Day, Whitsunday, Corpus Christi)

How does it work?

Day-view just requesting a stringlist and handles them specific.

All other views:
the plugin generate allday-events with a wrong uid. The views care about
and may do something special (if wanted).

As in good calendar is these automatic generated fake-events should displayed
on top of all other events. this will done due the overloaded db-class asks FIRST
the plugins and THEN for real events. So these fake-events are always at front
of eventlist.