Merge pull request #593 from jonboulle/master

travis: drop go 1.4

Author: jonboulle

.travis.yml

@@ -4,10 +4,6 @@ language: go
 
 matrix:
   include:
-    - go: 1.4.2
-      install:
-        - go get golang.org/x/tools/cmd/cover
-        - go get golang.org/x/tools/cmd/vet
     - go: 1.5.1
     - go: 1.6