restructure ontology course 05

[stap-m]

Summary of the discussion

Based on #167

The new course focuses on "how to become an OEO developer". The old couse goes to legacy. It will be transferred to another course later, focussing on using the OEO.

closes #167

PR-Assignee

• [ ] 🐙 Follow the workflow in CONTRIBUTING.md
• [ ] 📝 Update the CHANGELOG.md
• [ ] 🐙 Assign a reviewer to the PR

Reviewer

• [ ] 🐙 Follow the Reviewer Guidelines
• [ ] 🐙 Provided feedback and show sufficient appreciation for the work done