Travis go 1.8

Former-commit-id: 6cec1776862e3b8e753e13afa00341182ea3abf9

.travis.yml

@@ -2,5 +2,6 @@ language: go
 
 go:
     - go1.7
+    - go1.8
 
 go_import_path: gopkg.in/kataras/iris.v6

response_writer.go

@@ -61,6 +61,8 @@ type ResponseWriter interface {
 	http.Flusher
 	http.Hijacker
 	http.CloseNotifier
+	// breaks go 1.7 as well as the *PushOptions.
+	// New users should upgrade to 1.8 if they want to use Iris.
 	http.Pusher
 
 	Writef(format string, a ...interface{}) (n int, err error)