Error: Cannot find module './shared'
<p>I am attempting to get a Node app with MongoLab working on Heroku. I get the following message in my Heroku logs: "Error: Cannot find module './shared'".  I have uninstalled and reinstalled node_modules several times and have also installed a "shared" module, to no avail. The app runs fine on localhost. Is there anything I'm missing?</p>