NEW YORK (Reuters) - As uncertainty swirls around any criminal prosecution of George Zimmerman, the shooter of 17-year-old Trayvon Martin in an Orlando suburb, one option that remains open to Martin's family is a civil case. Zimmerman could be shielded from prosecution under Florida's 2005 "Stand Your Ground Law," which gives immunity to people who use deadly force in their own defense without clear evidence of malice. The same law also says a person who uses such force is immune from civil action. ...