BRUSSELS (Reuters) - It started as an informal dinner among European finance ministers more than 14 years ago and has steadily gained prominence under its veteran president, Jean-Claude Juncker. But on Monday the grey-haired Juncker, 58, handed the reins of the Eurogroup to a polished 46-year-old Dutchman, promising a new approach to how economic policy among the 17 euro zone countries is shaped and decided. ...