heroku stuff

server.js

@@ -39,12 +39,14 @@ app.get('/app', (req, res)=>{
     }
 });
 
-mongoose.connect('mongodb://localhost:27017/auth');
+const mongoURI = process.env.MONGODB_URI || 'mongodb://localhost:27017/auth';
+mongoose.connect(mongoURI);
 
 mongoose.connection.once('open', ()=>{
     console.log('connected to mongo');
 })
 
-app.listen(3000, ()=>{
+const port = process.env.PORT || 3000;
+app.listen(port, ()=>{
     console.log('listening');
 });