Fix frontend not updating publicConfig.json

This changes the handshake sequence to use “bootTime” (a unique key
based off the time) to make sure the frontend configuration matches the
current one. If not, the client pulls the update and validates before
requesting the listing.

lib/server.js

@@ -4,6 +4,7 @@ var url = require('url');
 var mime = require('mime');
 var io = require('socket.io');
 
+var util = require('./util');
 var logger = require('./logger');
 
 var config = require('../config.json');
@@ -65,7 +66,8 @@ function handleRequest(req, res) {
 		var publicConfig = {
 			categories: categories,
 			graphDuration: config.graphDuration,
-			servers: servers
+			servers: servers,
+			bootTime: util.getBootTime()
 		};
 
 		res.write('setPublicConfig(' + JSON.stringify(publicConfig) + ');');