Fix 401 Unauthorized errors + empty logstash password check

[braunbearded]

Pull Request Template

Description

This fixes Issue #39. Additionally I updated the Readme to reference the files which includes the logstash passwords and therefore needs to be updated. A small script automates the password update if someone wants to use it.

Type of change

• [x] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [x] This change requires a documentation update

How Has This Been Tested?

run: docker-compose up and check the log for 401 Responses from the es01 container

Checklist:

• [x] Code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] New and existing unit tests pass locally with my changes
• [ ] Any dependent changes have been merged and published in downstream modules

[braunbearded]

Turns out request which use the credentials in 50-outputs.pfelk need higher privileges or something so I changed the user back to elastic and updated the rest accordingly. Before that I got requests with 403 status code in the logs.

[a3ilson]

@braunbearded - awesome/thanks! I’ll update in the next day or two as I’m currently traveling.