Add Gitter integration with Travis

Author: pthariensflame

.travis.yml

@@ -3,3 +3,10 @@ osx_image: xcode7.1
 before_install: true
 install: true
 script: script/cibuild Concurrent Concurrent-iOS
+notifications:
+  webhooks:
+    urls:
+      - https://webhooks.gitter.im/e/1d781e1bcbabade5de35
+    on_success: always
+    on_failure: always
+    on_start: always