BRUSSELS, Feb 15 (Reuters) - Transparency campaigners have hauled the European Union's executive to court for withholding documents about free trade talks with India, intensifying pressure on the bloc to make its policy-making less secretive. The lawsuit, lodged with the EU's second-highest court on Tuesday, accuses the EU Commission of breaking transparency and democracy rules by refusing to disclose to campaigners details of plans shared with EU industry on how to open Indian markets.