People take part in a demonstration on May 5, 2013 in Paris, called by Jean-Luc Melenchon, leader of Front de Gauche (Left Front) left wing party, to protest 'against the austerity, against the finance and to ask for a Sixth Republic'. When France's president Francois Hollande swept to power on May 2012 on a wave of discontent, he could hardly have imagined that a year later he would be the most unpopular president in modern French history.