Adds manifest.json to examples folder (#3536)

* Revert "Revert "[examples] Add manifest.json""

This reverts commit c65336e63b.

* Revert "Revert "Do not use now-examples anymore""

This reverts commit ac72e944a7.

* Update nowignore

* Fix join

* Fix JSON

* Fix header

* Replace manifest.json with @now/frameworks

* Adjust readmes

* Adjust .nowignore

* Update scully

* Fix description

* Update examples/create-react-app/src/App.js

Co-Authored-By: Shu Ding <ds303077135@gmail.com>

* Update readme

* Add websites

* Use https

* Adjust example URL

* Change order

Co-authored-by: Shu Ding <ds303077135@gmail.com>

examples/create-react-app/api/date.go

@@ -0,0 +1,12 @@
+package handler
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+)
+
+func Handler(w http.ResponseWriter, r *http.Request) {
+	currentTime := time.Now().Format(time.RFC850)
+	fmt.Fprintf(w, currentTime)
+}