performance close to handlers if no bindings but even if bindings except service (new feature is that we can bind functions as well) is x1.1 faster than the previous mvc implementation - make BaseController (so and C) optionally but not break the existing APIs that using iris.C or mvc.C

Former-commit-id: a26a8f836894c061e0f435df8ac1c2c534f0ee48

_benchmarks/iris-mvc2/main.go

@@ -0,0 +1,17 @@
+package main
+
+/// TODO: remove this on the "master" branch, or even replace it
+// with the "iris-mvc" (the new implementatioin is even faster, close to handlers version,
+// with bindings or without).
+
+import (
+	"github.com/kataras/iris"
+	"github.com/kataras/iris/_benchmarks/iris-mvc2/controllers"
+	"github.com/kataras/iris/mvc2"
+)
+
+func main() {
+	app := iris.New()
+	mvc2.New().Controller(app.Party("/api/values/{id}"), new(controllers.ValuesController))
+	app.Run(iris.Addr(":5000"), iris.WithoutVersionChecker)
+}