By Manuel Ausloos PARIS (Reuters) – Hadj Benhalima sized up the building in front of him then took a run at the wall, pushed off its surface with one foot, twisted around in mid-air and reached out to flick a switch a few metres off the ground. A clunk and brief second later, the glaring outdoor sign of the currency exchange store went dark, one of many shop-front illuminations the wiry 21-year-old and his fellow Parkour athletes switched off one night last week in a bid to combat energy waste. “There are many shop windows lit up at night and for no good reason. So given I can turn them off, I…