Update Go build to use 1.7.3

Diwaker Gupta · Diwaker Gupta · commit 710d12eade8c · 2016-11-23T09:50:12.000-08:00
diff --git a/.travis.yml b/.travis.yml
@@ -2,7 +2,7 @@ language: go
 
 go:
   - 1.6.3
-  - 1.7
+  - 1.7.3
 
 install:
   - go get -u golang.org/x/oauth2
