title: Issue with docker compose
body: <p>The issue I am having is that after I try and run docker-compose up, after everything is downloaded(python dependencies) docker-compose will just hang on</p>
  
  <pre><code>Recreating sensorarray_web_1...
  Attaching to sensorarray_web_1
  </code></pre>
  
  <p>My directory structure looks like like this:</p>
  
  <pre><code>.
   ├── docker-compose.yml
   ├── Dockerfile
   ├── requirements.txt
   └── sensoryarray.py
  </code></pre>
  
  <p>Dockerfile:</p>
  
  <pre><code>FROM python:2.7
  WORKDIR /code
  ADD requirements.txt /code/
  RUN pip install -r requirements.txt
  ADD . /code
  CMD python sensorarray.py
  </code></pre>
  
  <p>docker-compose.yml</p>
  
  <pre><code>web:
   build: .
   command: python sensorarray.py
  ports:
   - "5000:5000"
  volumes:
   - .:/code
  </code></pre>
  
  <p>sensoryarray.py:</p>
  
  <pre><code>from flask import Flask
  app = Flask(__name__)
  
  @app.route('/')
  def hello():
      return 'Hello World!'
  
  if __name__ == "__main__":
      app.run(host="0.0.0.0", debug=True)
  </code></pre>
  
  <p>I also ran the docker hello world example and it seems to be working fine.</p>