General repository cleanup

[MaximMoinat]

Todo's:

• [x] Remove prias/erspc concept files. These are redundant with the new pioneer concepts
• [ ] Restructure the repo, e.g. split out the other folder
• [ ] Add a default Achilles run R notebook
• [ ] Create data source specific loading scripts (currently one for erspc and one for ab)
• [ ] List mapped data sources and their status (e.g. not started, started, loaded, validated)
• [ ] Update use of custom vocabulary across datasources