Fixed Bug & support http2 Push

[devfeel]

• Fixed Bug: Request.IsAJAX check X-Requested-With Contains XMLHttpRequest
• New Feature: Response support http2 Push
• How To:
  • how to query slow response in your app?

  func main() {
  	app := dotweb.Classic("/home/logs/wwwroot/")
  
  	// deal slow response, use default handler
  	// default Handler will write timeout-response in dotweb's log file
  	// also you can implement your own handlers, like write logs with http api
  	app.UseTimeoutHook(dotweb.DefaultTimeoutHookHandler, time.Second * 10)
  
  	app.HttpServer.GET("/index", func(ctx dotweb.Context) error{
  		return ctx.WriteString("welcome to my first web!")
  	})
  
  	//begin server
  	err := app.StartServer(80)
      fmt.Println("dotweb.StartServer error => ", err)
  }

• 2019-01-02 18:00