add gitter webhook to travis

.travis.yml

@@ -9,3 +9,11 @@ branches:
 
 before_script: "npm install -g codeclimate-test-reporter"
 script: "make test-travis"
+
+notifications:
+  webhooks:
+    urls:
+      - https://webhooks.gitter.im/e/acf1870e9d223c65e8d5
+    on_success: change
+    on_failure: always
+    on_start: false