title: How use `echo` in a command in docker-compose.yml to handle a colon (":") sign?
body: <p>Here is my <code>docker-compose.yml</code>,</p>
  <pre><code>elasticsearch:
    ports:
    - 9200:9200/tcp
    image: elasticsearch:2.4
   volumes:
    - /data/elasticsearch/usr/share/elasticsearch/data:/usr/share/elasticsearch/data
   command: /bin/bash -c “echo 'http.cors.enabled: true' &gt; /usr/share/elasticsearch/config/elasticsearch.yml&quot;
  </code></pre>
  <p>it throws the error:</p>
  <blockquote>
  <p>Activating (yaml: [] mapping values are not allowed in this context at line 7, column 49</p>
  </blockquote>
  <p>Looks as if I cannot use the colon sign <code>:</code> in <code>command</code>, is this true?</p>