culdesac in cgi: prefer culdesacs over regular crossings

This gives more control if a culdesac description is more concise than
a crossing name, e.g. "Blücherplatz/Sackgassenende" is better than
"Blücherplatz/(Blücherplatz - Johanniterstr.)/(Blücherplatz - Zossener
Str.)".
data update (culdesac reorganization)

Moved some culdesac records from ignore section to non-ignore section,
to utilize the changed logic in bbbike.cgi (culdesac have precedence
over crossings)
HOWTO_edit_bbbike_data: doc for culdesac
regenerated some html pages
cul-de-sac-candidates.pl helper script: use new file

It's now culdesac-orig, not comments_misc-orig anymore.
bbd.pod: changed sample for "ignore" directive

culdesac is not anymore in comments_misc-orig, use busroute_n records
instead.
BBBikeTest: new standard option -simulate-skips
cgi-test.t: allow new option -simulate-skips
cgi-test.t: culdesac test done with XPath

More reliable than like_html(). Also another test case was added, to
test culdesac over crossing name priority (with Bluecherplatz as
sample).
data update (after survey in Wilmersdorf)
culdesac creation: preserve global directives
data update (finished systematic culdesac checks)
cgi-test.t: (not_)on_crossing_pref_page works also for English
bbbike.cgi, culdesac handling: handle default name

Default name is "Sackgassenende", with English translation.
cgi-test.t: test case for default and English culdesac names
culdesac data: make use of default names

This shrinks file size from about 30000 bytes to 22000 bytes.
data update (minor)
check_cont: works also outside data directory

Default for str_cont_ausnahme has now full path. Also added more
diagnostics in case the file could not be loaded.