Customize widoco_sections

• Intro: similar to https://gitlab.hrz.tu-chemnitz.de/s4308286--tu-dresden.de/listdb/-/tree/2-update-main-readme-md#listdb-ontology
• Documentation
• Abstract
• References:
  • https://gitlab.hrz.tu-chemnitz.de/s4308286--tu-dresden.de/listdb/-/tree/2-update-main-readme-md#references
  • and others on ListDB
  • re-used ontologies?