Include airbrake-go dependency in Travis install step.
diff --git a/.travis.yml b/.travis.yml
index 2c5ec79..d5a559f 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,3 +6,4 @@
 install:
   - go get github.com/stretchr/testify
   - go get github.com/stvp/go-udp-testing
+  - go get github.com/tobi/airbrake-go