add a very simple example on JWT and move the previous to the 'overview' sub folder

_examples/auth/jwt/basic/main.go

@@ -0,0 +1,44 @@
+package main
+
+import (
+	"time"
+
+	"github.com/kataras/iris/v12"
+	"github.com/kataras/iris/v12/middleware/jwt"
+)
+
+func main() {
+	app := iris.New()
+	// With AES-GCM (128) encryption:
+	// j := jwt.HMAC(15*time.Minute, "secret", "itsa16bytesecret")
+	// Without extra encryption, just the sign key:
+	j := jwt.HMAC(15*time.Minute, "secret")
+
+	app.Get("/", generateToken(j))
+	app.Get("/protected", j.VerifyMap(), protected)
+
+	app.Listen(":8080")
+}
+
+func generateToken(j *jwt.JWT) iris.Handler {
+	return func(ctx iris.Context) {
+		token, err := j.Token(iris.Map{
+			"foo": "bar",
+		})
+		if err != nil {
+			ctx.StopWithStatus(iris.StatusInternalServerError)
+			return
+		}
+
+		ctx.HTML(`Token: ` + token + `<br/><br/>
+		<a href="/protected?token=` + token + `">/secured?token=` + token + `</a>`)
+	}
+}
+
+func protected(ctx iris.Context) {
+	ctx.Writef("This is an authenticated request.\n\n")
+
+	claims := jwt.Get(ctx).(iris.Map)
+
+	ctx.Writef("foo=%s\n", claims["foo"])
+}