reorganization of _examples and add some new examples such as iris+groupcache+mysql+docker

Former-commit-id: ed635ee95de7160cde11eaabc0c1dcb0e460a620

_examples/caddy/server1/main.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"github.com/kataras/iris/v12"
+	"github.com/kataras/iris/v12/mvc"
+)
+
+func main() {
+	app := iris.New()
+
+	templates := iris.HTML("./views", ".html").Layout("shared/layout.html")
+	app.RegisterView(templates)
+
+	mvc.New(app).Handle(new(Controller))
+
+	// http://localhost:9091
+	app.Listen(":9091")
+}
+
+// Layout contains all the binding properties for the shared/layout.html
+type Layout struct {
+	Title string
+}
+
+// Controller is our example controller, request-scoped, each request has its own instance.
+type Controller struct {
+	Layout Layout
+}
+
+// BeginRequest is the first method fired when client requests from this Controller's root path.
+func (c *Controller) BeginRequest(ctx iris.Context) {
+	c.Layout.Title = "Home Page"
+}
+
+// EndRequest is the last method fired.
+// It's here just to complete the BaseController
+// in order to be tell iris to call the `BeginRequest` before the main method.
+func (c *Controller) EndRequest(ctx iris.Context) {}
+
+// Get handles GET http://localhost:9091
+func (c *Controller) Get() mvc.View {
+	return mvc.View{
+		Name: "index.html",
+		Data: iris.Map{
+			"Layout":  c.Layout,
+			"Message": "Welcome to my website!",
+		},
+	}
+}