Tutorial improvement

[martinkarbon]

• [ ] Denodo:
  • move content away from the slides? The slides are deprecated clarify "Selection" and add screenshot to the presentation, ore remove it? clarify "Unfold properties"
• [ ] Check that the prefix ex is preserved in the mapping files
• [ ] Change titles of the sidebar
• [ ] Add Mapping of Assistant Professor (university-no-pk.obda, university-no-fk.obda, university-manual-ssn.obda, university-canonical.obda )
• [x] Dremio - mapping assertions: missing ex prefix? (not sure)
• [ ] Mapping/URI-templates: check the mapping-target-syntax(if they are correct)
• [ ] Migrate the last commits in the ontop-tutorial (Dremio)

[Muffexx]

One additional needed improvement:

• [x] Dremio - add download link for uni2.json file