The Panther by Nelson DeMille Grand Central Publishing, $27.99, 629 pages, ISBN 978-0-446-58084-7 We’re taking a quantum leap of the imagination with this week’s Mysterious Book Report, from eighteenth century Sweden, to twenty-first century Yemen.  Yemen, for those wanting a little bit of remedial geography, (yeah, me too . . .) is located to the south of Saudi Arabia and shares a long, undefined boarder with it called the