Added GARS graticule and a corresponding example.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@2384 822214bb-dcf7-4c8d-a767-17ae0fb20d88
Corrected documentation in GARSGraticule example.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@2385 822214bb-dcf7-4c8d-a767-17ae0fb20d88