Renault's new electric Twingo fits easily into the French carmaker's portfolio. It is a modern mini passenger car meant for urban European drivers, but it also tells a story about changes in the broader auto industry .   Renault developed the new Twingo over a breakneck 21 months in Shanghai, following an initial design phase in France .  The car is now in production in Slovenia, arriving this month at dealers with a price tag just under €20,000 ($23,000). The continent-hopping Twingo is a snapshot of a hypercompetitive auto industry and its new center of gravity in China. There, many legacy carmakers are developing new models by focusing on speed, cost and technology.  Germany's Merz seeks China reset as trade imbalance widens To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video "The real…