Use name of the cluster as web title

Set the title attribute of the web interface page to the name of the
cluster.

packages/master/src/Master.js

@@ -641,6 +641,7 @@ class Master {
 			fs.readFile(path.join(__dirname, "..", "web", "index.html"), "utf8").then((content) => {
 				res.type("text/html");
 				res.send(content
+					.replace(/__CLUSTER_NAME__/g, res.app.locals.master.config.get("master.name"))
 					.replace(/__WEB_ROOT__/g, webRoot)
 					.replace(/__STATIC_ROOT__/g, staticRoot)
 					.replace(/__MAIN_BUNDLE__/g, mainBundle)

packages/master/web/index.html

@@ -4,7 +4,7 @@
 		<meta charset="utf-8" />
 		<meta name="viewport" content="width=device-width, initial-scale=1" />
 		<meta name="theme-color" content="#2a2a2a" />
-		<title>Clusterio</title>
+		<title>__CLUSTER_NAME__</title>
 		<style>
 			html {
 				color: #fff;