Judgment of the Court (First Chamber) of 15 September 2005 in Case C-258/04: Reference for a preliminary ruling from the Cour de travail de Liège in Office national de l'emploi v Ioannis Ioannidis (Job-seekers — European citizenship — Principle of non-discrimination — Article 39 EC — Tideover allowances for young people seeking their first employment — Grant conditional on completion of secondary education in the Member State concerned)