Synthesis and Polymerization of an Optically Active Bifunctional Disiloxane. 1. Preparation of Optically Active and Highly Stereoregular Poly [$$(1 S)-1-(1-naphthyl)-1-phenyl-3, 3-dimethyldisiloxane-1, 3-diyl$$ ethylene] by Polyaddition via Hydrosilylat