Dockerfile and docker-compose not updating with new instructions : <p>When I try to build a container using docker-compose like so </p>

<pre><code>nginx:
  build: ./nginx
  ports:
    - "5000:80"
</code></pre>

<p>the COPY instructions isnt working when my Dockerfile simply 
looks like this</p>

<pre><code>FROM nginx

#Expose port 80
EXPOSE 80

COPY html /usr/share/nginx/test

#Start nginx server
RUN service nginx restart
</code></pre>

<p>What could be the problem?</p>
