By Luc Olinga GM’s premium brand seeks to revive cachet with design of a new ultra-luxurious car that will cause a stir. General Motors (GM) – Get General Motors Company Report finally seems to have a vehicle that will propel it back into the ranks of manufacturers of premiere high-end luxury vehicles to compete with the likes of Rolls-Royce and Bentley. It is the club of manufacturers of the artisanal vehicles, one would be tempted to say. The principle of the brands belonging to this club is that each car leaving their factory is different from the others. The cars don’t look alike at all. E…