Bulent Celebi, the ebullient chairman of AirTies Wireless Networks, has been talking to us about proprietary mesh networks and powerline as a spare backhaul option in WiFi for so long, that it’s hard to imagine that we have never written about it. But it has taken this long for someone to buy into the concept and for the product to be completed for a live implementation and readied for launch. The fact that the someone is Sky, one of the two largest pay TV operators in Europe, will make everyone want to understand just what it has achieved and how this system works on its new Sky Q set top. The significance is that when you add client steering, a…