Test with go1.7
diff --git a/.travis.yml b/.travis.yml
index 5ef5d72..f134724 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -2,5 +2,5 @@
 go:
     - 1.4.3
     - 1.5.3
-    - 1.6
-    - tip
+    - 1.6.3
+    - 1.7