Resource lookup timeout causes Travis IC to fail test.

Hi,
 Today the Travic CI system failed a test. It looks like the DTD lookup
failed. You can see the failed test for 307.12

https://travis-ci.org/pgjdbc/pgjdbc/builds/60815064

 Will it be useful if I created a PR with an XML catalog containing the
resource to enable local resolution ? It would mean false positives of
this nature do not crop up again.

Regards,
Jeremy