Day.deleteAll ()
function deletes all childobjects of a day (recursive!)

Sourcecode in Day/objectFunctions.js:
1:   function deleteAll() {
2:      for (var i=this.size();i>0;i--) {
3:         var story = this.get(i-1);
4:         story.deleteAll();
5:         story.remove();
6:      }
7:      return true;
8:   }