Add port npm config var

package.json

@@ -1,9 +1,11 @@
 {
   "name": "npmcdn.com",
   "version": "1.0.0",
+  "description": "An HTTP server for files in npm packages",
   "author": "Michael Jackson",
-  "license": "MIT",
-  "main": "server.js",
+  "config": {
+    "port": 5000
+  },
   "dependencies": {
     "cors": "^2.7.1",
     "express": "^4.13.4",

server.js

@@ -1,17 +1,14 @@
-var port = process.env.PORT || 5000
-
 var express = require('express')
 var createRequestHandler = require('npm-http-server').createRequestHandler
 var cors = require('cors')
 
+var port = process.env.PORT || process.env.npm_package_config_port
 var app = express()
 
 app.disable('x-powered-by')
 app.use(cors())
 app.use(express.static('public', { maxAge: 60000 }))
-app.use(
-  createRequestHandler()
-)
+app.use(createRequestHandler())
 
 app.listen(port, function () {
   console.log('Server started on port ' + port + '. Ctrl+C to quit')