Case T-496/15 P: Judgment of the General Court of 13 May 2016 — CX v Commission (Appeal — Appeal — Civil service — Officials — Disciplinary proceedings — Disciplinary measure — Downgrading — Rights of the defence — Articles 4 and 6 of the Staff Regulations — Article 9 of Annex IX to the Staff Regulations — Principle of proportionality — Manifest error of assessment)