Increase Travis CI JVM heap size
diff --git a/.travis.yml b/.travis.yml
index 25342ee..af8bd9e 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,6 +3,8 @@
   - oraclejdk7
   - openjdk7
   - openjdk6
+env:
+  - JAVA_OPTS=-Xmx1024m
 before_script:
   - ulimit -n 64000
   - ulimit -u 64000