add uint8 parameter type, and mvc and hero - this commit may be a point of tutorial on how to add a completely new type from scratch to the hero for future contributors

Former-commit-id: dc7a7e6c97ef0c644a22e92072e4bdb98ae10582

_examples/routing/dynamic-path/main.go

@@ -48,6 +48,13 @@ func main() {
 	// -9223372036854775808 to 9223372036854775807
 	//
 	// +------------------------+
+	// | {param:uint8}          |
+	// +------------------------+
+	// uint8 type
+	// 0 to 255
+	//
+	//
+	// +------------------------+
 	// | {param:uint64}         |
 	// +------------------------+
 	// uint64 type
@@ -146,6 +153,12 @@ func main() {
 		ctx.Writef("Hello id: %d looking for friend id: ", id, friendid)
 	}) // this will throw e 504 error code instead of 404 if all route's macros not passed.
 
+	// :uint8 0 to 255.
+	app.Get("/ages/{age:uint8 else 400}", func(ctx iris.Context) {
+		age, _ := ctx.Params().GetUint8("age")
+		ctx.Writef("age selected: %d", age)
+	})
+
 	// Another example using a custom regexp and any custom logic.
 	latLonExpr := "^-?[0-9]{1,3}(?:\\.[0-9]{1,10})?$"
 	latLonRegex, err := regexp.Compile(latLonExpr)