adds comments

Author: Rafael Alfaro

build-server.js

@@ -1,5 +1,7 @@
 const nodeStatic = require('node-static');
 const file = new nodeStatic.Server('./build');
+//Heroku uses random port and forwards to port 80 automatically
+//port 3000 is for running locally
 const port = process.env.PORT || 3000;
 console.log('\nListening on port: ' + port);
 require('http').createServer(function(request, response) {