FIX: BirthdayListViewHelper did not sort correctly

BirthdayListViewHelper used MySQL's DAYOFYEAR() function to determine sort order. This function is leap-year agnostic and therefore led to problems with people born in leap years. This is now fixed.
Merge branch 'master' of github.com:VolksmissionFreudenstadt/vmfds_kool

Conflicts:
	Classes/ViewHelpers/BirthdayListViewHelper.php