Start of the internal cmd

gen website examples is the first command that I should finish soon because we need it for the website's "Recipe" page. Two more html query-relative dependencies added.


Former-commit-id: 04b7f8bb968cbc3c441e2a09a4aa525b10cd4aca

_examples/beginner/hello-world/main.go

@@ -10,5 +10,5 @@ func main() {
 	app.Handle("GET", "/", func(ctx context.Context) {
 		ctx.HTML("<b> Hello world! </b>")
 	})
-	app.Run(iris.Addr(":8080"))
+	app.Run(iris.Addr(":8080"), iris.WithTray)
 }