base.t: new -v (verbose) switch
mmap + coord2ptr + net2name file building

coord2ptr and net2name files now depend only on mmap file (could help
to ensure consistency between these three files).

Make sure that mmap file building is atomic (by building first in a
temporary file).
check-forever target: don't lock while sleeping

So other jobs (e.g. a testing cron job) have a chance to operate.
cgi, draw_route_from_fh: "Dateiformat nicht erkannt" page

The error page was never shown, because Route.pm returns an empty
RealCoords arrayref in the error case, which was not checked.

With test case in cgi-mechanize-upload.t.
thumbnails-googlemaps target: don't overwhelm Google, sleep between
thumbnail requests
strassen-build.t: use special cacheprefix

Formerly, the test script wrote the mmap file in a special location
below t/tmp, but the corresponding coord2ptr+net2name cache files were
written to central /tmp, interefering with StrassenNetz::CNetFile's
cache files. This was probably the reason for the occasional
segfaults during nightly testing.
data update (minor)