Updated the chg_to_date_yyyywwd.patch with additional tests (because it
works not only for 'D' pattern but also for all day patterns like 'Day'
or 'DY'). Added the necessary documentation change.
(The fix_to_char_yyyywwd.patch from
f4e740a8de3ad1e762a28f6ff253ea4f%40four-two.de is still up-to-date)