Prepare for 21.3 release (#2057)

* Prepare for release

* Add to changelog recent PRs

* add missing changelog items and update contributing docs

* Add 2061

* add 2060 to changelog

* Add 20.12.3 to changelog

* Add #2064 to changelog

* Do not show host and port in README

* Add some documentation PRs to changelog

* add new decorators to changelog

* Add 2063

* Add some PRs to misc

examples/http_redirect.py

@@ -0,0 +1,51 @@
+from sanic import Sanic, response, text
+
+
+HTTP_PORT = 9999
+HTTPS_PORT = 8888
+
+http = Sanic("http")
+http.config.SERVER_NAME = f"localhost:{HTTP_PORT}"
+https = Sanic("https")
+https.config.SERVER_NAME = f"localhost:{HTTPS_PORT}"
+
+
+@https.get("/foo")
+def foo(request):
+    return text("foo")
+
+
+@https.get("/bar")
+def bar(request):
+    return text("bar")
+
+
+@http.get("/<path:path>")
+def proxy(request, path):
+    url = request.app.url_for(
+        "proxy",
+        path=path,
+        _server=https.config.SERVER_NAME,
+        _external=True,
+        _scheme="http",
+    )
+    return response.redirect(url)
+
+
+@https.listener("main_process_start")
+async def start(app, _):
+    global http
+    app.http_server = await http.create_server(
+        port=HTTP_PORT, return_asyncio_server=True
+    )
+    app.http_server.after_start()
+
+
+@https.listener("main_process_stop")
+async def stop(app, _):
+    app.http_server.before_stop()
+    await app.http_server.close()
+    app.http_server.after_stop()
+
+
+https.run(port=HTTPS_PORT, debug=True)