Add some _examples in the main repository too.

Former-commit-id: 98895c34115ec2076b431332f0ffe9645adf7590

_examples/examples/hello-world/main.go

@@ -0,0 +1,20 @@
+package main
+
+import (
+	"gopkg.in/kataras/iris.v6"
+	"gopkg.in/kataras/iris.v6/adaptors/httprouter"
+)
+
+func main() {
+	app := iris.New()
+	// Adapt the "httprouter", faster,
+	// but it has limits on named path parameters' validation,
+	// you can adapt "gorillamux" if you need regexp path validation!
+	app.Adapt(httprouter.New())
+
+	app.HandleFunc("GET", "/", func(ctx *iris.Context) {
+		ctx.Writef("hello world\n")
+	})
+
+	app.Listen(":8080")
+}