drop support for older than 1.4 go versions

.travis.yml

@@ -1,8 +1,5 @@
 language: go
 go:
-  - 1.1
-  - 1.2
-  - 1.3
   - 1.4
   - 1.5
   - 1.6
@@ -14,6 +11,8 @@ script:
   - go get github.com/shiena/ansicolor
 
   # run standard go tests
+  - go vet ./...
+  - go fmt ./...
   - go test -v
   - go test -race