You cannot hear the people sing in Andrew Davies’ adaptation of Victor Hugo’s classic novel Les Misérables, and that is just fine. The six-episode series, which aired on the BBC last year and is now premiering on PBS in the United States, is in turn a sumptuous and horrifying exploration of the lives of the French working class and poor that spans the decades of early the 1800s (notably between revolutions). If the title doesn’t tip you off, an opening scene of the corpses of horses and men strewn across the battlefield of Waterloo will. But …