GOSNELL: THE UNTOLD STORY OF AMERICA’S MOST PROLIFIC SERIAL KILLER By Ann McElhinney and Phelim McAleer Regnery, $27.99, 256 pages I followed the Kermit Gosnell murder trial in 2013, which was covered by the local Philadelphia media, but ignored largely by the national media. Now journalists and documentary filmmakers Ann McElhinney and Phelim McAleer offer a…