By Sedara Oluwadara Neymar scored twice as Paris St-Germain made it two Ligue 1 wins from two under new boss Christophe Galtier with a resounding defeat of Montpellier.   While Kylian Mbappe saw a first-half penalty saved, PSG went ahead through Falaye Sacko's own goal.     Neymar scored from the spot and headed his second to put the hosts three up.   Wahbi Khazri and Enzo Tchato were on target for Montpellier but Mbappe and Renato Sanches goals ensured another emphatic win for PSG.   In Galiter's first home game as boss, PSG dominated from the start, earning