TWO sets of numbers tell a contradictory story about the euro zone. Economic data point to improvements by the month, even by the day: growth is picking up and the borrowing costs of even the most indebted countries keep falling. The crisis is over, say some Eurocrats. By contrast, polls ahead of this month’s European elections point to political upheaval. Voters are exasperated with their governments and with Europe; anti-establishment groups are on the rise and may come top in some places. . .