Add Slack integration.

Author: rolftimmermans

.travis.yml

@@ -1,13 +1,12 @@
 language: php
-
 php:
-  - 5.3
-  - 5.4
-  - 5.5
-  - 5.6
-  - hhvm
-
+- 5.3
+- 5.4
+- 5.5
+- 5.6
+- hhvm
 before_script: composer install
-
 script: phpunit --process-isolation test/unit
-
+notifications:
+  slack:
+    secure: uttJ78cpkV9czhoKXtAoop8UBWPVtF+fwKlKS47c4EW7ZfVx9jAII2yLb5yZjdLDnM7YAluujUBIqyESvwLY0h7azLsorSIEqNt9GlBi4B7DSGAdo46lFbqsdjrLwM1gOhiP7Fl4hFiQ2+jA9Fsj3W2yZ6rbF7endv7Gx5FMlFg=