Add PureJSON renderer (#694)

Closes #693

render/json_17.go

@@ -0,0 +1,28 @@
+// Copyright 2018 Gin Core Team.  All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+// +build go1.7
+
+package render
+
+import (
+	"net/http"
+
+	"github.com/gin-gonic/gin/json"
+)
+
+type PureJSON struct {
+	Data interface{}
+}
+
+func (r PureJSON) Render(w http.ResponseWriter) error {
+	r.WriteContentType(w)
+	encoder := json.NewEncoder(w)
+	encoder.SetEscapeHTML(false)
+	return encoder.Encode(r.Data)
+}
+
+func (r PureJSON) WriteContentType(w http.ResponseWriter) {
+	writeContentType(w, jsonContentType)
+}