make travis install gx deps

.travis.yml

@@ -13,4 +13,5 @@ env:
 install: true
 
 script:
+  - make deps
   - go test ./p2p/...

Makefile

+gx:
+	go get -u github.com/whyrusleeping/gx
+	go get -u github.com/whyrusleeping/gx-go
+
+deps: gx
+	gx --verbose install --global