Two new config values in section "ShopSettings" provide some oder_nr
tweaking:
o OrderIdBase:
use a start value when generating order_nrs (start from 123456 instead
of 1)
o OrderIdUseYear
1. Prepend year to order_nr (4 digits), pattern:

2. Reset order_nr if year changes (On newyear's day 200923456 will be
followed by 2010