further validation of instances on PR/commit

[lzehl]

Things to check:

• namespace convention for type, atid, props
• instance located in wrong subfolder (e.g. ProgrammingLanguage instance in AnalysisTechnique folder)
• mismatch between attype and atid (e.g. type:...ProgrammingLanguage, atid:...instances/analysisTechnique/xxx.jsonld)
• alphabetically ordering of properties (convention check, maybe should just be done for you)
• convention check for name vs atid vs filename (for terminologies, licenses, contentType)
  • atid_basename == lower camelCase of name (no spaces, / replaced with _; proper names and abbreviations are to be kept)
  • filename == atid_basename with .jsonld extension (no spaces, / replaced with _)
• general validation against schema

[lzehl]

should also be covered in contribution guidelines on docu

[Raphael-Gazzotti]

The validation pipeline has been updated, although the documentation still requires updating.