SEOUL (Reuters) – Shares of key Samsung Group [SAGR.UL] companies opened higher on Thursday, after a South Korean court rejected the special prosecutor’s request for an arrest warrant for Samsung Group leader Jay Y. Lee. Shares of Samsung Electronics Co Ltd were up 2.5 percent while Samsung C&T Corp shares were 4.1 percent higher as of 0003 GMT, outperforming a 0.7 percent rise for the broader market . …