There’s nothing terribly original about the farmhouse-under-seige scenario.   Precedents include such classics as “Night of the Living Dead” (1968), “Straw Dogs” (1971) or even the Three Little Pigs and the Big Bad Wolf. What makes director/co-scripter/star John Krasinski’s impressive “A Quiet Place” (2018) uniquely distinctive are the rules imposed upon this particular farmhouse-under-siege scenario.  This…