Add Travis CI definition, as a test.
Add Travis CI definition, as a test.

adaxi/freeciv-web,tltneon/freeciv-web,tltneon/freeciv-web,tltneon/freeciv-web,adaxi/freeciv-web,andreasrosdal/freeciv-web,tltneon/freeciv-web,tltneon/freeciv-web,andreasrosdal/freeciv-web,tltneon/freeciv-web,adaxi/freeciv-web,adaxi/freeciv-web,adaxi/freeciv-web,andreasrosdal/freeciv-web,andreasrosdal/freeciv-web,andreasrosdal/freeciv-web