- added screenshot file format to options menu

- more cleanup from things discovered with valgrind.
- added an environment variable to use with openal so it is possible to specify which sound device to use if needed down the road

source/shared_lib/include/graphics/gl/context_gl.h

@@ -30,7 +30,7 @@ protected:
 
 public:
 	ContextGl();
-	virtual ~ContextGl(){}
+	virtual ~ContextGl();
 
 	virtual void init();
 	virtual void end();