Introduce go chi web framework as frontend of macaron, so that we can move routes from macaron to chi step by step (#7420)

* When route cannot be found on chi, go to macaron

* Stick chi version to 1.5.0

* Follow router log setting

vendor/github.com/go-chi/chi/middleware/nocache.go

@@ -0,0 +1,58 @@
+package middleware
+
+// Ported from Goji's middleware, source:
+// https://github.com/zenazn/goji/tree/master/web/middleware
+
+import (
+	"net/http"
+	"time"
+)
+
+// Unix epoch time
+var epoch = time.Unix(0, 0).Format(time.RFC1123)
+
+// Taken from https://github.com/mytrile/nocache
+var noCacheHeaders = map[string]string{
+	"Expires":         epoch,
+	"Cache-Control":   "no-cache, no-store, no-transform, must-revalidate, private, max-age=0",
+	"Pragma":          "no-cache",
+	"X-Accel-Expires": "0",
+}
+
+var etagHeaders = []string{
+	"ETag",
+	"If-Modified-Since",
+	"If-Match",
+	"If-None-Match",
+	"If-Range",
+	"If-Unmodified-Since",
+}
+
+// NoCache is a simple piece of middleware that sets a number of HTTP headers to prevent
+// a router (or subrouter) from being cached by an upstream proxy and/or client.
+//
+// As per http://wiki.nginx.org/HttpProxyModule - NoCache sets:
+//      Expires: Thu, 01 Jan 1970 00:00:00 UTC
+//      Cache-Control: no-cache, private, max-age=0
+//      X-Accel-Expires: 0
+//      Pragma: no-cache (for HTTP/1.0 proxies/clients)
+func NoCache(h http.Handler) http.Handler {
+	fn := func(w http.ResponseWriter, r *http.Request) {
+
+		// Delete any ETag headers that may have been set
+		for _, v := range etagHeaders {
+			if r.Header.Get(v) != "" {
+				r.Header.Del(v)
+			}
+		}
+
+		// Set our NoCache headers
+		for k, v := range noCacheHeaders {
+			w.Header().Set(k, v)
+		}
+
+		h.ServeHTTP(w, r)
+	}
+
+	return http.HandlerFunc(fn)
+}