Pull request: beta client squashed

Merge in DNS/adguard-home from beta-client-2 to master

Squashed commit of the following:

commit b2640cc49a6c5484d730b534dcf5a8013d7fa478
Merge: 659def862 aef4659e9
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Tue Dec 29 19:23:09 2020 +0300

    Merge branch 'master' into beta-client-2

commit 659def8626467949c35b7a6a0c99ffafb07b4385
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Tue Dec 29 17:25:14 2020 +0300

    all: upgrade github actions node version

commit b4b8cf8dd75672e9155da5d111ac66e8f5ba1535
Author: Vladislav Abdulmyanov <v.abdulmyanov@adguard.com>
Date:   Tue Dec 29 16:57:14 2020 +0300

    all: beta client squashed

internal/home/middlewares.go

@@ -40,3 +40,18 @@ func limitRequestBody(h http.Handler) (limited http.Handler) {
 		h.ServeHTTP(w, r)
 	})
 }
+
+// wrapIndexBeta returns handler that deals with new client.
+func (web *Web) wrapIndexBeta(http.Handler) (wrapped http.Handler) {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		h, pattern := Context.mux.Handler(r)
+		switch pattern {
+		case "/":
+			web.handlerBeta.ServeHTTP(w, r)
+		case "/install.html":
+			web.installerBeta.ServeHTTP(w, r)
+		default:
+			h.ServeHTTP(w, r)
+		}
+	})
+}