Add a config test.

tests/apps/config/Procfile

@@ -0,0 +1 @@
+web: node web.js

tests/apps/config/check_deploy

@@ -0,0 +1,3 @@
+#!/bin/bash
+set -e; output="$(curl -s $1)"; echo $output; test "$output" == "config-test"
+

tests/apps/config/package.json

@@ -0,0 +1,11 @@
+{
+  "name": "node-example",
+  "version": "0.0.1",
+  "dependencies": {
+    "express": "2.5.x"
+  },
+  "engines": {
+    "node": "0.8.x",
+    "npm": "1.1.x"
+  }
+}

tests/apps/config/post-deploy

@@ -0,0 +1,8 @@
+#!/bin/bash
+set -ex;
+
+REMOTE=$1
+REPO=$2
+
+ssh $REMOTE config:set $REPO CONFTEST=config-test
+

tests/apps/config/web.js

@@ -0,0 +1,12 @@
+var express = require('express');
+
+var app = express.createServer(express.logger());
+
+app.get('/', function(request, response) {
+  response.send(process.env.CONFTEST);
+});
+
+var port = process.env.PORT || 5000;
+app.listen(port, function() {
+  console.log("Listening on " + port);
+});