restore hello-world example for go1.9 👪

relative to https://github.com/kataras/iris/pull/673


Former-commit-id: 3df6becbb40b14c4073b99255c75537e5046ffe8

_examples/hello-world/main_go19.go

@@ -0,0 +1,35 @@
+// +build go1.9
+
+package main
+
+import (
+	"github.com/kataras/iris"
+)
+
+func main() {
+	app := iris.Default()
+
+	// Method:   GET
+	// Resource: http://localhost:8080/
+	app.Handle("GET", "/", func(ctx iris.Context) {
+		ctx.HTML("<b>Hello world!</b>")
+	})
+
+	// same as app.Handle("GET", "/ping", [...])
+	// Method:   GET
+	// Resource: http://localhost:8080/ping
+	app.Get("/ping", func(ctx iris.Context) {
+		ctx.WriteString("pong")
+	})
+
+	// Method:   GET
+	// Resource: http://localhost:8080/hello
+	app.Get("/hello", func(ctx iris.Context) {
+		ctx.JSON(iris.Map{"message": "Hello iris web framework."})
+	})
+
+	// http://localhost:8080
+	// http://localhost:8080/ping
+	// http://localhost:8080/hello
+	app.Run(iris.Addr(":8080"))
+}

_examples/http-listening/listen-addr/main.go

@@ -9,7 +9,7 @@ func main() {
 	app := iris.New()
 
 	app.Get("/", func(ctx context.Context) {
-		ctx.HTML("<h1>Hello World!/</h1>")
+		ctx.HTML("<h1>Hello World!</h1>")
 	})
 
 	// http://localhost:8080

_examples/http-listening/listen-addr/omit-server-errors/main.go

@@ -9,7 +9,7 @@ func main() {
 	app := iris.New()
 
 	app.Get("/", func(ctx context.Context) {
-		ctx.HTML("<h1>Hello World!/</h1>")
+		ctx.HTML("<h1>Hello World!</h1>")
 	})
 
 	err := app.Run(iris.Addr(":8080"), iris.WithoutServerError(iris.ErrServerClosed))