Merge pull request #4 from lestard/0.x

Fixes #3 and the "Gtk-WARNING **: cannot open display" errors on on
Travis CI that it was likely referring to.

* lestard/0.x:
  Add travis config to fix failing tests

Author: cbeams

.travis.yml

@@ -2,3 +2,7 @@ language: java
 
 jdk:
   - oraclejdk8
+
+before_install:
+- export DISPLAY=:99.0
+- sh -e /etc/init.d/xvfb start