Fix dual app bug

[ericuldall]

ExpressMVC should be able to run multiple app instances on different ports and/or ip's without issue, however there is currently an issue doing so. I believe this stems from the app configs being shared across EMVC globally. We need to make sure each app gets a unique version of express with it's own unique options.

Example:

var ExpressMVC = require('express_mvc');
var app_a = new ExpressMVC.App({port: 8080});
var app_b = new ExpressMVC.App({port: 8081});
var router = new ExpressMVC.Router('/');
router.addRoute(new router.Route('GET', '/', function(req, res){ res.write('test'); res.end();}));

app_a.addRouter(router);
app_b.addRouter(router);

app_a.listen();
app_b.listen();