Case T-298/09: Judgment of the General Court (SecondChamber) of 20 September 2011 — Evropaïki Dynamiki v Commission (Public service contracts — Community tendering procedure — Supply of external services for educational programmes — Award of the contract to several tenderers — Tenderer’s ranking — Action for annulment — Obligation to state the reasons on which the decision is based — Grounds for exclusion from the contract award procedure — Article 93(1)(f) of the Financial Regulation — Tender validity period — Non-contractual liability)