cache control headers

express.js

@@ -2,4 +2,10 @@
 var express = require('express');
 var app = express();
 
+// enable client-side caching of 60s by default
+app.use(function(req, res, next){
+  res.header('Cache-Control','public,max-age=60');
+  next();
+});
+
 module.exports = app;