[dockerfile] test new config stuff

tests/apps/dockerfile/index.js

@@ -8,6 +8,10 @@ app.get('/', function(request, response) {
   response.send('Hello World!')
 })
 
+app.get('/env/:key', function(request, response) {
+  response.send(process.env[request.params["key"]])
+})
+
 app.listen(app.get('port'), function() {
   console.log("Node app is running at localhost:" + app.get('port'))
 })