Perl bindings tests fail if PG:dbname=autotest isn't available

[Even Rouault]

I had to disable PostgreSQL in the trunk_trusty CI branch (at least for now), and since then I get the following failure:

​https://s3.amazonaws.com/archive.travis-ci.org/jobs/145109528/log.txt

t/00-measures-04.t .. 1/? PQconnectdb failed.
FATAL:  database "autotest" does not exist
 at /home/travis/build/rouault/gdal_coverage/gdal/swig/perl/blib/lib/Geo/GDAL.pm line 1364.
	Geo::GDAL::OpenEx('PG:dbname=autotest', 'ARRAY(0x24b9b80)') called at /home/travis/build/rouault/gdal_coverage/gdal/swig/perl/blib/lib/Geo/OGR.pm line 927
	Geo::OGR::Open('PG:dbname=autotest', 1) called at t/00-measures-04.t line 50
# Looks like your test exited with 255 just after 1.

Would it be possible to modify the test so that it skips gracefully if opening pg:dbname=autotest fails ?

[Ari Jolma]

Modified in r34727.

[Even Rouault]

Thanks