title: While importing 'myapp.app' an import error was raised
body: <p>I'm building a flask application, located in a subdirectory within my project called <code>myapp</code>. Running <code>gunicorn --bind 0.0.0.0:$PORT myapp.app:app</code> works fine, no errors, regardless of what FLASK_APP is set to. When I try to use Flask's CLI, however, it fails to find my app (reasonable), but when I set FLASK_APP to <code>myapp.app.</code>, it appears to be doubling up the import path, resulting in an import error:</p>
  <pre><code>FLASK_APP=myapp.app flask run
   * Serving Flask app 'myapp.app' (lazy loading)
   * Environment: production
     WARNING: This is a development server. Do not use it in a production deployment.
     Use a production WSGI server instead.
   * Debug mode: off
  Usage: flask run [OPTIONS]
  Try 'flask run --help' for help.
  
  Error: While importing 'myapp.myapp.app', an ImportError was raised.
  </code></pre>
  <p>How can I solve this? Is this a bug in Flask?</p>