SOUTH KINGSTOWN, R.I. – Are you familiar with the Battle of Iwo Jima? You probably aren’t unless you know a lot about World War II or have seen the 2006 war drama “Letters from Iwo Jima” from direcotr Clint Eastwood. That’s exactly why World War II Foundation President Tim Gray made a documentary about it. And judging from his sixth regional Emmy Award for Best Historical Documentary Film, that’s also why people loved it.