new script: create_cooked_bbd
use create_cooked_bbd in data/Makefile
osm2bbd-postprocess: rationalized up-to-date checks
reduce_streets: don't search in @Strassen::datadirs
create_cooked_bbd: don't search in @Strassen::datadirs and copy global directives
new osm2bbd-postprocess targets: strassen_cooked and fragezeichen_cooked
data update