Adding elk log analysis vm

Adding an ELK container stack so we can analyze customer log files.

To test add the following to gitlab-vagrant.yml:

- name: log-analysis
  memory: 4272
  ip_address: 192.168.15.53
  elk: yes

Then run vagrant up log-analysis and follow the instructions to use.

Note that I also refactored the README.md for easier comprehension with all of the additional services.