By Mike Dolan LONDON (Reuters) -What matters in U.S. and global markets today By Mike Dolan, Editor-At-Large, Finance and Markets A looming U.S. government shutdown is casting a shadow over the final day of a stellar third quarter for most world markets. However, there appears to be little trepidation apart from fretting over a data vacuum that could be left by the likely postponement of the monthly jobs report. U.S. President Donald Trump and his Democratic opponents appeared to make little progress a ...