run integration test on CI

Author: ocadaruma

.travis.yml

@@ -1,10 +1,17 @@
 language: scala
 
+env:
+  - GCLOUD_SERVICE_KEY_LOCATION="${HOME}/gcloud-service-key.json"
+
 scala:
   - 2.11.8
 
 jdk:
   - oraclejdk8
 
+before_script:
+  - echo ${GCLOUD_SERVICE_KEY} | base64 --decode > ${GCLOUD_SERVICE_KEY_LOCATION}
+
 script:
   - sbt test
+  - sbt it:test