title: multiple django requirements with docker
body: <p>i am new to docker and i am having issues building a new image when using Django with multiple requirements. It's failing to pip install them.</p>
  
  <p>I am getting </p>
  
  <pre><code>Could not open requirements file: [Errno 2] No such file or directory: 'requirements/local.txt'
  Service 'web' failed to build: The command '/bin/sh -c pip install -r requirements/local.txt' returned a non-zero code: 1`
  </code></pre>
  
  <p>My code is :</p>
  
  <pre><code>FROM python:2.7
  ENV PYTHONUNBUFFERED 1
  RUN mkdir /code
  WORKDIR /code
  COPY requirements/local.txt /code/
  RUN pip install -r requirements/local.txt
  COPY . /code/
  </code></pre>
  
  <p>What is the proper syntax no make this work when running <code>docker-compose up</code> ?</p>
  
  <p>cheers</p>