Problem:

If you delete the VHOST file because you want to use port-based deployment (i.e. you're installing dokku in a VM), I expect the application to be deployed at http://hostname:port as per documentation.
But the current release deploys the app on http://app-name.hostname, ignoring the fact that no VHOST is set.

Steps to reproduce:

1. Install dokku
2. Remove /home/dokku/VHOST
3. Deploy sample node-js-app
4. In the git push output you'll see

=====> Application deployed:
http://node-js-app.<hostname>

Expected outcome:

=====> Application deployed:
http://<hostname>:<port>

Possible fix:

dokku url node-js-app returns the wrong hostname although the logic is correct.
The issue is in dokku nginx:build-config node-js-app as the logic to deploy on a port is executed only when the NO_VHOST variable is set (https://github.com/progrium/dokku/blob/master/plugins/nginx-vhosts/commands#L32)

Setting it manually works as expected:

root@combotest:~# env NO_VHOST=1 dokku nginx:build-config node-js-app
-----> NO_VHOST set, deleting node-js-app/VHOST
-----> NO_VHOST set, deleting nginx.conf
-----> NO_VHOST set, reloading nginx after nginx.conf deletion

I suspect this NO_VHOST variable should be set after deploy before calling nginx:build-config, but it isn't.

If you can point out which is the best place to set this variable, I can do a pull request myself.