“1 Article 296(2) of Council Directive 2006/112/EC of28 November 2006 on the common system of value added tax must be interpreted as laying down exhaustively all the cases in which a member state may exclude a farmer from the common flat-rate scheme for farmers. 2 Article 296(2) of Directive 2006/112 must be interpreted as meaning that farmers who are found to be recovering substantially more as members of the common flat-rate scheme for farmers than they would if they were subject to the normal value added tax arrangements or the simplified value added tax arrangements cannot constitute a category of farmers within the meaning of that provision.”