Remove System V init instructions that no longer work

[MarkEWaite]

Remove System V init instructions that no longer work

Link to the Jenkins instructions for managing system properties.

Use consistent headings and improve the phrasing a little.

Testing done

Will confirm the page renders reasonably in GitHub.

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1. Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
2. Ensure that the pull request title represents the desired changelog entry
3. Please describe what you did
4. Link to relevant issues in GitHub or Jira
5. Link to relevant pull requests, esp. upstream and downstream changes
6. Ensure you have provided tests - that demonstrates feature works or fixes the issue