Case C-581/17: Judgment of the Court (Grand Chamber) of 26 February 2019 (request for a preliminary ruling from the Finanzgericht Baden-Württemberg — Germany) — Martin Wächtler v Finanzamt Konstanz (Reference for a preliminary ruling — Agreement between the European Community and the Swiss Confederation on the free movement of persons — Transfer by a natural person of his domicile from a Member State to Switzerland — Taxation of unrealised capital gains with respect to shares in a company — Direct taxation — Freedom of movement of self-employed persons — Equal treatment)