Add docker image for secured version and README with the details

[dlumbrer]

This commit adds the needed files for the image creation process of the 6.8.6 Kibiter secured version. For Bitergia purposes.

[dlumbrer]

Updated @sduenas, thanks

[dlumbrer]

LGTM but I found the next error building the image:

Step 25/30 : RUN ./opt/kibana/bin/kibana | sleep 200 > /tmp/run_kibana_log.txt
 ---> Running in 4af05fbcda26
Browserslist: caniuse-lite is outdated. Please run next command `npm update caniuse-lite browserslist`

events.js:174
      throw er; // Unhandled 'error' event
      ^

Error: write EPIPE
    at WriteWrap.afterWrite (net.js:782:14)
Emitted 'error' event at:
    at Socket.onerror (_stream_readable.js:691:12)
    at Socket.emit (events.js:194:15)
    at onwriteError (_stream_writable.js:431:12)
    at onwrite (_stream_writable.js:456:5)
    at _destroy (internal/streams/destroy.js:40:7)
    at Socket.dummyDestroy [as _destroy] (internal/process/stdio.js:11:34)
    at Socket.destroy (internal/streams/destroy.js:32:8)
    at WriteWrap.afterWrite (net.js:784:10)

This is a "controlled" error because we force to init Kibiter in the image creation process, forcing Kibiter to bundle its scripts (optimize process) and then launching the next time instantly. The error appears because we "kill" Kibiter.

While running the container I also found the next error, so the container fails before it starts:

kibiter_1        | /docker_entrypoint.sh: line 67: syntax error: unexpected end of file

This is part of the docker-compose I use to run the container:

kibiter:
  restart: on-failure:5
  image: integration-6.8.6
  environment:
    - PROJECT_NAME=Development
    - NODE_OPTIONS=--max-old-space-size=1000
    - ELASTICSEARCH_URL=https://admin:admin@elasticsearch:9200
    - ELASTICSEARCH_USER=admin
    - ELASTICSEARCH_PASSWORD=admin
  links:
    - elasticsearch
  ports:
    - 5601:5601

I solved it, I added by mistake an "else" instead of a "fi", sorry about that