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

Former-commit-id: ed635ee95de7160cde11eaabc0c1dcb0e460a620

_examples/routing/sitemap/main_test.go

@@ -0,0 +1,18 @@
+package main
+
+import (
+	"testing"
+
+	"github.com/kataras/iris/v12"
+	"github.com/kataras/iris/v12/httptest"
+)
+
+func TestSitemap(t *testing.T) {
+	const expectedFullSitemapXML = `<?xml version="1.0" encoding="utf-8" standalone="yes"?><urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"><url><loc>http://localhost:8080/home</loc><lastmod>2019-12-13T21:50:33+02:00</lastmod><changefreq>hourly</changefreq><priority>1</priority></url><url><loc>http://localhost:8080/articles</loc><changefreq>daily</changefreq></url><url><loc>http://localhost:8080/path1</loc></url><url><loc>http://localhost:8080/path2</loc></url></urlset>`
+
+	app := newApp()
+	app.Configure(iris.WithSitemap(startURL))
+
+	e := httptest.New(t, app)
+	e.GET("/sitemap.xml").Expect().Status(httptest.StatusOK).Body().Equal(expectedFullSitemapXML)
+}